As a user, after copy or repo version creation there are no advisories with the same id
Similar to #4295, just for copy and any other repo version creation case when units are added.
Each repo version should have no more than one UpdateRecord with the same
Decide which UpdateRecord to keep based on the criteria defined in #4295.
- awaits a decision on the thread: https://www.redhat.com/archives/pulp-dev/2019-June/msg00077.html