chore(deps): update pascalgn/automerge-action action to v0.15.5

Author: renovate[bot]

.github/workflows/automerge.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: automerge
-        uses: pascalgn/automerge-action@v0.12.0
+        uses: pascalgn/automerge-action@eb68b061739cb9d81564f8e812d0b3c45f0fb09a # v0.15.5
         env:
           # Allows this merge to trigger other actions
           GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"