👷 add dependabot automerge github action

.github/workflows/dependabot_automerge.yml

@@ -0,0 +1,32 @@
+name: Dependabot auto-merge & auto-approve
+on: pull_request
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  dependabot:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' }}
+    steps:
+      - name: Dependabot metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@v1
+        with:
+          github-token: "${{ secrets.PAT }}"
+      - name: Enable auto-merge for Dependabot PRs
+        id: auto-merge
+        if: |
+          ${{ steps.metadata.outputs.update-type == 'version-update:semver-patch'
+          || steps.metadata.outputs.update-type == 'version-update:semver-minor'}}
+        run: gh pr merge --auto --merge "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{ secrets.PAT }}
+      - name: Approve a PR
+        if: ${{ steps.auto-merge.conclusion == 'success' }}
+        run: gh pr review --approve "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{ secrets.PAT }}