Bump reitermarkus/automerge from 2.7.0 to 2.8.0

Bumps [reitermarkus/automerge](https://github.com/reitermarkus/automerge) from 2.7.0 to 2.8.0.
- [Release notes](https://github.com/reitermarkus/automerge/releases)
- [Commits](42e67be9e2...634d0a4b51)

---
updated-dependencies:
- dependency-name: reitermarkus/automerge
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/automerge.yml

@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Enable auto-merge
-        uses: reitermarkus/automerge@42e67be9e28a0d0b50407cc3a1c07076e3aa6834
+        uses: reitermarkus/automerge@634d0a4b51134c163eee182ac9aa79133eb33e8d
         with:
           token: ${{ secrets.HOMEBREW_GITHUB_PUBLIC_REPO_TOKEN }}
           merge-method: merge