ci: also auto-merge major github-actions bumps (safe, no code changes)

Author: dacrab

.github/workflows/auto-merge-dependabot.yml

@@ -24,3 +24,9 @@ jobs:
         run: gh pr merge --auto --squash "${{ github.event.pull_request.html_url }}"
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Enable auto-merge for major github-actions updates
+        if: steps.metadata.outputs.update-type == 'version-update:semver-major' && steps.metadata.outputs.package-ecosystem == 'github-actions'
+        run: gh pr merge --auto --squash "${{ github.event.pull_request.html_url }}"
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}