[TASK] Migrate backport and documentation workflows to shared reusable workflows

.github/workflows/backport.yml

@@ -11,9 +11,6 @@ permissions:
 
 jobs:
   backport:
-    uses: TYPO3-Documentation/.github/.github/workflows/reusable-backport.yml@9d884304b1a5cdeeb2e21349a5bbfe52da5548d5
+    uses: TYPO3-Documentation/.github/.github/workflows/reusable-backport.yml@main
     with:
       label_pattern: "^backport (.+)$"
-    secrets:
-      APP_ID: ${{ secrets.APP_ID }}
-      APP_PRIVATE_KEY: ${{ secrets.APP_PRIVATE_KEY }}

.github/workflows/documentation.yml

@@ -1,17 +1,11 @@
 name: Test documentation
 
-on: [ push, pull_request ]
+on:
+  push:
+  pull_request:
 
 jobs:
-  tests:
-    name: Render documentation
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
-
-      - name: Test if the documentation will render without warnings
-        run: |
-          mkdir -p Documentation-GENERATED-temp \
-          && docker run --rm --pull always -v $(pwd):/project \
-             ghcr.io/typo3-documentation/render-guides:latest --config=Documentation --no-progress --minimal-test
+  render:
+    uses: TYPO3-Documentation/.github/.github/workflows/reusable-test-documentation.yml@main
+    with:
+      render-flags: '--no-progress --minimal-test'