chore: add custom sync repo settings (#978)

Author: parthea

packages/google-auth/.github/sync-repo-settings.yaml

@@ -0,0 +1,20 @@
+# https://github.com/googleapis/repo-automation-bots/tree/main/packages/sync-repo-settings
+# Rules for main branch protection
+branchProtectionRules:
+# Identifies the protection rule pattern. Name of the branch to be protected.
+# Defaults to `main`
+- pattern: main
+  requiresCodeOwnerReviews: true
+  requiresStrictStatusChecks: true
+  requiredStatusCheckContexts:
+    - 'cla/google'
+    - 'OwlBot Post Processor'
+    - 'Kokoro system-3.7'
+    - 'Kokoro'
+permissionRules:
+  - team: actools-python
+    permission: admin
+  - team: actools
+    permission: admin
+  - team: yoshi-python
+    permission: push