"All format" cleanup policies disappear from repository assignments after editing

1. Create a cleanup policy for "all formats" with component age of 10 days
2. Assign this policy to a maven hosted repository
3. Edit the policy, and change the component age to 11 days

Observe that the policy has now entirely disappeared from the maven repository's configuration.  It isn't just unassigned, it is completely missing, and cannot be reassigned.