.github: bump dependabot/fetch-metadata from 1.5.1 to 1.6.0

Bumps [dependabot/fetch-metadata](https://github.com/dependabot/fetch-metadata) from 1.5.1 to 1.6.0.
- [Release notes](https://github.com/dependabot/fetch-metadata/releases)
- [Commits](dependabot/fetch-metadata@v1.5.1...v1.6.0)

---
updated-dependencies:
- dependency-name: dependabot/fetch-metadata
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/dependabot-automerge-js.yml

@@ -18,7 +18,7 @@ jobs:
     steps:
       - name: Dependabot metadata
         id: metadata
-        uses: dependabot/fetch-metadata@v1.5.1
+        uses: dependabot/fetch-metadata@v1.6.0
         with:
           github-token: "${{ secrets.GITHUB_TOKEN }}"