CI: Backport to release branches (#100067)

* update backport and release comms

* Backport to release branches and change docs source branch for publishing

* Add new workflows to CODEOWNERS

* Re-add removed line oops

* backport-testing -> grafana

* checkout grafana repo in backport action, reference repo / branch in reusable action

* generate -> create

.github/workflows/release-comms.yml

@@ -27,10 +27,18 @@ jobs:
     name: Setup and establish latest
     outputs:
       version: ${{ steps.output.outputs.version }}
+      release_branch: ${{ steps.output.outputs.release_branch }}
       dry_run: ${{ steps.output.outputs.dry_run }}
       latest: ${{ steps.output.outputs.latest }}
+      token: ${{ steps.output.outputs.token }}
     runs-on: ubuntu-latest
     steps:
+    - name: "Generate token"
+      id: generate_token
+      uses: tibdex/github-app-token@b62528385c34dbc9f38e5f4225ac829252d1ea92
+      with:
+        app_id: ${{ secrets.GRAFANA_DELIVERY_BOT_APP_ID }}
+        private_key: ${{ secrets.GRAFANA_DELIVERY_BOT_APP_PEM }}
       # The github-release action expects a `LATEST` value of a string of either '1' or '0'
     - if: ${{ github.event_name == 'workflow_dispatch' }}
       run: |
@@ -49,9 +57,51 @@ jobs:
         echo "latest: $LATEST"
         echo "version: $VERSION"
 
+        echo "release_branch=$(echo $VERSION | sed -s 's/^v/release-/g')" >> "$GITHUB_OUTPUT"
+        echo "token=${{ steps.generate_token.outputs.token }}" >> "$GITHUB_OUTPUT"
         echo "dry_run=$DRY_RUN" >> "$GITHUB_OUTPUT"
         echo "latest=$LATEST" >> "$GITHUB_OUTPUT"
         echo "version=$VERSION" >> "$GITHUB_OUTPUT"
+  create_next_release_branch_grafana:
+    name: Create next release branch (Grafana)
+    needs: setup
+    uses: ./.github/workflows/create-next-release-branch.yml
+    with:
+      ownerRepo: 'grafana/grafana'
+      source: ${{ needs.setup.outputs.release_branch }}
+    secrets:
+      token: ${{ needs.setup.outputs.token }}
+  create_next_release_branch_enterprise:
+    name: Create next release branch (Grafana Enterprise)
+    needs: setup
+    uses: ./.github/workflows/create-next-release-branch.yml
+    with:
+      ownerRepo: 'grafana/grafana'
+      source: ${{ needs.setup.outputs.release_branch }}
+    secrets:
+      token: ${{ needs.setup.outputs.token }}
+  migrate_prs_grafana:
+    needs:
+      - setup
+      - create_next_release_branch_grafana
+    uses: ./.github/workflows/migrate-prs.yml
+    with:
+      ownerRepo: 'grafana/grafana'
+      from: ${{ needs.setup.outputs.release_branch }}
+      to: ${{ needs.create_next_release_branch_grafana.outputs.branch }}
+    secrets:
+      token: ${{ needs.setup.outputs.token }}
+  migrate_prs_enterprise:
+    needs:
+      - setup
+      - create_next_release_branch_enterprise
+    uses: ./.github/workflows/migrate-prs.yml
+    with:
+      ownerRepo: 'grafana/grafana-enterprise'
+      from: ${{ needs.setup.outputs.release_branch }}
+      to: ${{ needs.create_next_release_branch_enterprise.outputs.branch }}
+    secrets:
+      token: ${{ needs.setup.outputs.token }}
   post_changelog_on_forum:
     needs: setup
     uses: ./.github/workflows/community-release.yml