CI: Enable automerge for dependabot/renovate

Signed-off-by: Tim Meusel <tim@bastelfreak.de>

Author: bastelfreak

.github/workflows/tests.yml

@@ -73,3 +73,20 @@ jobs:
         uses: re-actors/alls-green@release/v1
         with:
           jobs: ${{ toJSON(needs) }}
+
+  automerge:
+    name: Enable auto-merge
+    if: github.event_name == 'pull_request' && (github.event.pull_request.user.login == 'dependabot[bot]' || github.event.pull_request.user.login == 'renovate[bot]')
+    needs:
+      - tests
+    runs-on: ubuntu-24.04
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Enable auto-merge for PR
+        env:
+          GH_TOKEN: ${{ github.token }}
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          PR_HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        run: gh pr merge --auto --merge --match-head-commit "$PR_HEAD_SHA" "$PR_URL"