fix(ci): automatically merge Dependabot PRs upon approval again, again (#1119)

Refs: 92a0e33

Author: jenstroeger

.github/workflows/dependabot-automerge.yaml

@@ -14,6 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Merge Dependabot PR
-      run: gh pr merge --squash --delete-branch
+      run: gh pr merge --squash --delete-branch "$PR_URL"
       env:
+        PR_URL: ${{ github.event.pull_request.html_url }}
         GITHUB_TOKEN: ${{ secrets.DEPENDABOT_AUTOMERGE_TOKEN }}