[Dependencies]: Bump pascalgn/automerge-action from 0.16.3 to 0.16.4

Bumps [pascalgn/automerge-action](https://github.com/pascalgn/automerge-action) from 0.16.3 to 0.16.4.
- [Release notes](https://github.com/pascalgn/automerge-action/releases)
- [Commits](pascalgn/automerge-action@v0.16.3...v0.16.4)

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

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/merge-dependabot.yml

@@ -49,7 +49,7 @@ jobs:
 
       - name: "Auto-Merge"
         if: github.repository_owner == 'funfair-tech'
-        uses: pascalgn/[email protected].3
+        uses: pascalgn/[email protected].4
         env:
           GITHUB_TOKEN: ${{secrets.SOURCE_PUSH_TOKEN}}
           MERGE_METHOD: merge