ci: add auto-approve workflow

.github/workflows/auto-approve-own-prs.yml

@@ -0,0 +1,18 @@
+name: auto-approve
+
+on:
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  auto-approve:
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request' && github.event.pull_request.user.login == github.repository_owner
+    permissions:
+      pull-requests: write
+    steps:
+    - uses: actions/checkout@v4
+    - name: Auto-approve PR
+      run: gh pr review ${{ github.event.pull_request.number }} --approve
+      env:
+        GITHUB_TOKEN: ${{ github.token }}