build(deps): bump fastify/github-action-merge-dependabot (#771)

Bumps [fastify/github-action-merge-dependabot](https://github.com/fastify/github-action-merge-dependabot) from 3.11.2 to 3.12.0.
- [Release notes](https://github.com/fastify/github-action-merge-dependabot/releases)
- [Commits](fastify/github-action-merge-dependabot@v3.11.2...v3.12.0)

---
updated-dependencies:
- dependency-name: fastify/github-action-merge-dependabot
  dependency-version: 3.12.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

.github/workflows/dockerimage.yml

@@ -57,6 +57,6 @@ jobs:
       contents: write
     steps:
       - name: Automatically merge dependabot upgrades
-        uses: fastify/github-action-merge-dependabot@v3.11.2
+        uses: fastify/github-action-merge-dependabot@v3.12.0
         with:
           target: minor