Add Arborist step for branch approval enforcement

Added Arborist step to enforce branch approval rules.

Author: dluman

.github/workflows/main.yml

@@ -13,6 +13,16 @@ jobs:
     - uses: actions/checkout@v6.0.1
       with:
         fetch-depth: '0'
+    - name: Arborist
+      id: arborist
+      with:
+        branches: '["main"]'
+        min-approvals: 2
+        enforce-admins: false
+        team-roles: '{"technical-leaders": "maintain"}'
+      uses: dluman/arborist@v0.3.0
+      env:
+        GITHUB_TOKEN: ${{ secrets.ARBORIST_API_KEY }}
     - name: Setup Python
       if: always()
       uses: actions/setup-python@v6.1.0