Point to cpython/Doc/requirements.txt instead of duplicating it every time (python#3301)

Let's also do some alpha-sorting and small cleanup.

Signed-off-by: Rodrigo Tobar <[email protected]>

Author: rtobar

.overrides/upgrade-python-version.rst

@@ -23,9 +23,7 @@ We are currently in branch 3.12, and we want to update the strings from 3.13.
 
      git checkout tags/v3.13.0 -b 3.13.0
 
-#. Update the branch on the ``Makefile`` and check the ``requirements.txt`` from
-   ``./cpython/Doc`` directory, to see if upgrades on the modules like sphinx is
-   needed.
+#. Update the branch on the ``Makefile``
 
 #. Commit the update of the submodule change::
 
@@ -40,9 +38,14 @@ We are currently in branch 3.12, and we want to update the strings from 3.13.
      python -m venv env
      source env/bin/activate  # Windows: env\Scripts\activate.bat
      pip install -r requirements.txt
-     
-#. Verify that the docs build with the new versions you changed from
-   ``requirements.txt`` mainly the sphinx version::
+
+   .. note::
+      This might fail if some of our own requirements
+      conflict with cpython's. If so, find a way to fix
+      *our* requirements.
+
+#. Verify that the docs build with the new versions of the build requirements,
+   mainly the sphinx version::
 
      make build
 

requirements.txt

@@ -1,28 +1,18 @@
-docutils==0.21.2
+-r cpython/Doc/requirements.txt
+
+# Our own dependencies (alpha-sorted please)
 pip
-Pygments>=2.17.0
-PyICU
 polib
 pospell>=1.1
 potodo
 powrap>=1.0.2
-setuptools
-sphinx-intl>=2.3.0
 pre-commit
+Pygments>=2.17.0
+PyICU
+setuptools
 sphinx-autorun
 sphinxemoji
-sphinx-tabs==3.4.5
+sphinx-intl>=2.3.0
 sphinx-lint==0.7.0
+sphinx-tabs==3.4.5
 tabulate
-
-# from cpython/Doc/requirements.txt
-sphinx~=8.0.0
-
-blurb
-
-sphinxext-opengraph~=0.9.0
-sphinx-notfound-page~=1.0.0
-
-# The theme used by the documentation is stored separately, so we need
-# to install that as well.
-python-docs-theme>=2023.3.1,!=2023.7