[github actions] Permit to launch tests when backporting on maintenance branch (#7815)

Remove changelog so we don't have to laboriously label everything "skip news"
all the time.

Author: Pierre-Sassoulas

.github/workflows/backport.yml

@@ -0,0 +1,28 @@
+name: Backport
+on:
+  pull_request_target:
+    types:
+      - closed
+      - labeled
+
+permissions:
+  pull-requests: write
+
+jobs:
+  backport:
+    name: Backport
+    runs-on: ubuntu-latest
+    # Only react to merged PRs for security reasons.
+    # See https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request_target.
+    if: >
+      github.event.pull_request.merged && (
+        github.event.action == 'closed'
+        || (
+          github.event.action == 'labeled'
+          && contains(github.event.label.name, 'backport')
+        )
+      )
+    steps:
+      - uses: tibdex/backport@2e217641d82d02ba0603f46b1aeedefb258890ac
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/changelog.yml

@@ -3,7 +3,8 @@ name: changelog
 on:
   pull_request:
     types: [opened, synchronize, labeled, unlabeled, reopened]
-
+    branches-ignore:
+      - "maintenance/**"
 env:
   CACHE_VERSION: 1
   KEY_PREFIX: base-venv

.github/workflows/checks.yaml

@@ -4,7 +4,7 @@ on:
   push:
     branches:
       - main
-      - 2.*
+      - "maintenance/**"
   pull_request: ~
 
 env:

.github/workflows/primer-test.yaml

@@ -4,7 +4,7 @@ on:
   push:
     branches:
       - main
-      - 2.*
+      - "maintenance/**"
   pull_request:
     paths:
       - "pylint/**"

.github/workflows/primer_run_pr.yaml

@@ -16,8 +16,6 @@ on:
       - "!.github/workflows/primer_run_main.yaml"
       - "!.github/workflows/primer_comment.yaml"
       - "!tests/primer/packages_to_prime.json"
-    branches-ignore:
-      - "maintenance/**"
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}

.github/workflows/tests.yaml

@@ -4,7 +4,7 @@ on:
   push:
     branches:
       - main
-      - 2.*
+      - "maintenance/**"
   pull_request:
     paths-ignore:
       - doc/data/messages/**