Add auto-merge.yml (#4)

.github/dependabot.yml

@@ -0,0 +1,7 @@
+version: 2
+
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly

.github/workflows/auto-merge.yml

@@ -0,0 +1,28 @@
+name: Auto-Merge Bot PRs
+
+on: [pull_request]
+
+jobs:
+  wait-for-checks:
+    if: ${{ (github.actor == 'dependabot[bot]') || (github.actor == 'pre-commit-ci[bot]') }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Wait for other checks to succeed
+        uses: lewagon/wait-on-check-action@v1.2.0
+        with:
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
+          running-workflow-name: wait-for-checks
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+
+  auto-merge:
+    needs: [wait-for-checks]
+    permissions:
+      contents: write
+      pull-requests: write
+    runs-on: ubuntu-latest
+    steps:
+      - name: Enable auto-merge for Bot PRs
+        run: gh pr merge --auto --squash "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}