refactor: not pinning CI/CD dependencies (#66)

inspired by dependabot/fetch-metadata#246

Author: mfranzke

.github/workflows/99-auto-merge.yml

@@ -10,7 +10,7 @@ jobs:
     steps:
       - name: ⬇ Dependabot metadata
         id: metadata
-        uses: dependabot/fetch-metadata@v1.3.4
+        uses: dependabot/fetch-metadata@v1
         with:
           github-token: "${{ secrets.GITHUB_TOKEN }}"