Update policy-bot config

Author: jb3

kubernetes/namespaces/tooling/policy-bot/configmap.yaml

@@ -46,5 +46,12 @@ data:
     options:
       # The path within repositories to find the policy.yml file
       policy_path: .github/review-policy.yml
+
+      # Policy to use when a repository does not explicitly define one
+      shared_repository: .github
+      shared_policy_path: review-policies/core-developers.yml
+
       # The context prefix for status checks created by the bot
       status_check_context: "Review requirements"
+      # Expand users
+      expand_required_reviewers: true