feat: enable the auto-merge feature on dependabot prs

    - so we only have to approve them
    - enables the github feature auto-merge
    - only add this if tests pass

Signed-off-by: Robert Waffen <rwaffen@gmail.com>

.github/workflows/ci.yaml

@@ -106,3 +106,24 @@ jobs:
     name: Test suite
     steps:
       - run: echo Test suite completed
+
+  dependabot:
+    permissions:
+      contents: write
+    name: 'Dependabot auto-merge'
+    needs:
+      - tests
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' && github.event_name == 'pull_request'}}
+    steps:
+      - name: Dependabot metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@v2.2.0
+        with:
+          github-token: '${{ secrets.GITHUB_TOKEN }}'
+
+      - name: Enable auto-merge for Dependabot PRs
+        run: gh pr merge --auto --merge "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}