gh-35482: Update GitHub transition notices in the developer manual
    
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### 📚 Description

Updating the developer manual with the new workflow on github would take
some time. #35460 Meanwhile, we update the github transition notices in
the developer manual as the transition is over now.

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- [x] I have linked a relevant issue or discussion.
- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation accordingly.

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URL: #35482
Reported by: Kwankyu Lee
Reviewer(s): Matthias Köppe

Author: Release Manager

src/doc/en/developer/advanced_git.rst

@@ -8,12 +8,11 @@ Advanced Git
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 

src/doc/en/developer/git_trac.rst

@@ -8,12 +8,11 @@ Optional: Using the Git-Trac Command
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 

src/doc/en/developer/index.rst

@@ -6,12 +6,11 @@ Welcome to the Sage Developer's Guide!
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 

src/doc/en/developer/manual_git.rst

@@ -8,12 +8,11 @@ Using Git with the Sage Trac Server
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 
@@ -167,9 +166,9 @@ repository, use these commands::
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** After the
-    move, the Sage trac server [email protected]:sage.git will no longer be
-    available, but all branches will be available (in read-only mode) on
+    **Sage development moved to GitHub in February 2023.** After the move, the
+    Sage trac server [email protected]:sage.git no longer operates, but all
+    branches are available (in read-only mode) on
     https://github.com/sagemath/sagetrac-mirror.git.
 
 Instead of ``trac`` you can use any other name you want, of course.

src/doc/en/developer/reviewer_checklist.rst

@@ -8,12 +8,11 @@ The reviewer's check list
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 

src/doc/en/developer/trac.rst

@@ -8,12 +8,11 @@ The Sage Trac Server
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 
@@ -46,8 +45,8 @@ the :trac:`Sage trac timeline <timeline>`.
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.**
-    All functions of our Trac server will be taken over by our main repository,
+    **Sage development moved to GitHub in February 2023.**
+    All functions of our Trac server were taken over by our main repository,
     https://github.com/sagemath/sage.
 
 
@@ -354,10 +353,8 @@ other tests that run on GitHub Actions.
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.**
-    After the move, the patch buildbot will no longer be available; the three
-    workflows above are considered a full replacement. If you miss any features
-    of the patch buildbot, please report this in :trac:`33457`.
+    **Sage development moved to GitHub in February 2023.**
+    After the move, the patch buildbot no longer operates.
 
 The following are some other relevant issues:
 

src/doc/en/developer/walk_through.rst

@@ -8,12 +8,11 @@ Sage Development Process
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.
 
@@ -124,9 +123,8 @@ actually takes place.
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.**
-    After the move, https://github.com/sagemath/sage.git will be the
-    primary repository.
+    **Sage development moved to GitHub in February 2023.**
+    Now https://github.com/sagemath/sage.git is the primary repository.
 
 .. _section-walkthrough-branch:
 

src/doc/en/developer/workflows.rst

@@ -8,12 +8,11 @@ Distributed Development
 
 .. WARNING::
 
-    **Sage development is scheduled to move to GitHub in February 2023.** The exact
-    date will be announced in `<https://groups.google.com/g/sage-devel>`_. After
-    the transition, some parts of this guide (especially those related with `the
-    Sage Trac server <https://trac.sagemath.org>`_) will become obsolete and be
-    updated according to the new workflow on GitHub. See our `transition guide from Trac to
-    GitHub
+    **Sage development moved to GitHub in February 2023.** After the transition,
+    some parts of this guide (especially those related with `the Sage Trac
+    server <https://trac.sagemath.org>`_) became obsolete and need to be
+    updated according to the new workflow on GitHub. See our `transition guide
+    from Trac to GitHub
     <https://github.com/sagemath/trac-to-github/blob/master/docs/Migration-Trac-to-Github.md>`_
     for the preliminary version of the workflow.