Bump pascalgn/automerge-action from 0.15.2 to 0.15.3 (JabRef#8803)

Bumps [pascalgn/automerge-action](https://github.com/pascalgn/automerge-action) from 0.15.2 to 0.15.3.
- [Release notes](https://github.com/pascalgn/automerge-action/releases)
- [Commits](pascalgn/automerge-action@v0.15.2...v0.15.3)

---
updated-dependencies:
- dependency-name: pascalgn/automerge-action
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/automerge.yml

@@ -21,7 +21,7 @@ jobs:
         with:
           github-token: "${{ secrets.GITHUB_TOKEN }}"
       - name: Merge pull requests
-        uses: pascalgn/automerge-action@v0.15.2
+        uses: pascalgn/automerge-action@v0.15.3
         if: steps.waitforstatuschecks.outputs.status == 'success'
         env:
           MERGE_METHOD: "merge"