After upgrade to 4.3.1: "duplicate key value violates unique constraint" during content proxy sync

@drallay You are absolutely right. I have even mentioned the second error there. 74f3e561 is CentOS Stream 8 BaseOS and ac46caa8 is AlmaLinx 8 BaseOS. It’s the same issue.

To be continued in Sync errors on all syncs including the initial sync between new katello server and content proxy