Do not require approvals on pull requests

See apache/celix#398 (review) . Celix is a small project which doesn't need this setting yet

.asf.yaml

@@ -44,5 +44,6 @@ github:
   protected_branches:
     asf-site: {}
     master:
-      required_pull_request_reviews: {}
+      required_pull_request_reviews:
+        required_approving_review_count: 0