blacken all gen'd libs (#6792)

* blacken all gen'd libs

Author: crwilcox

google/cloud/container_v1/__init__.py

@@ -26,8 +26,4 @@ class ClusterManagerClient(cluster_manager_client.ClusterManagerClient):
     enums = enums
 
 
-__all__ = (
-    'enums',
-    'types',
-    'ClusterManagerClient',
-)
+__all__ = ("enums", "types", "ClusterManagerClient")