Enable async GC for all

Fixes #569

endpoints/v1/index.py

@@ -236,9 +236,6 @@ def update_images(namespace, repository):
       # Make sure the repo actually exists.
       abort(404, message='Unknown repository', issue='unknown-repo')
 
-    logger.debug('GCing repository')
-    model.repository.garbage_collect_repository(namespace, repository)
-
     # Generate a job for each notification that has been added to this repo
     logger.debug('Adding notifications for repository')