chore: setup branch policy for v1 (#1575)

* chore: setup branch policy for v1

* have v1 branch protection in a separate section

Author: shobsi

.github/sync-repo-settings.yaml

@@ -20,6 +20,23 @@ branchProtectionRules:
     - 'cover'
     - 'Kokoro presubmit'
     - 'Kokoro windows'
+- pattern: v1
+  requiresCodeOwnerReviews: true
+  requiresStrictStatusChecks: false
+  requiredStatusCheckContexts:
+    - 'OwlBot Post Processor'
+    - 'conventionalcommits.org'
+    - 'cla/google'
+    - 'docs'
+    - 'lint'
+    - 'mypy'
+    - 'unit (3.9)'
+    - 'unit (3.10)'
+    - 'unit (3.11)'
+    - 'unit (3.12)'
+    - 'cover'
+    - 'Kokoro presubmit'
+    - 'Kokoro windows'
 permissionRules:
   - team: actools-python
     permission: admin