build(deps): bump fastify/github-action-merge-dependabot

Bumps [fastify/github-action-merge-dependabot](https://github.com/fastify/github-action-merge-dependabot) from 3.0.2 to 3.1.3.
- [Release notes](https://github.com/fastify/github-action-merge-dependabot/releases)
- [Commits](fastify/github-action-merge-dependabot@v3.0.2...v3.1.3)

---
updated-dependencies:
- dependency-name: fastify/github-action-merge-dependabot
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/ci.yml

@@ -123,6 +123,6 @@ jobs:
       pull-requests: write
       contents: write
     steps:
-      - uses: fastify/github-action-merge-dependabot@v3.0.2
+      - uses: fastify/github-action-merge-dependabot@v3.1.3
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}