Description of problem:

When we trigger an optimized sync or a sync where no content is added, it is not audited (sync Audit is missing). That may cause problems when tasks are wiped out - we lose the information when a repo was synced last.

How reproducible:

always

Is this issue a regression from an earlier version:

no, present in 6.17.0, 6.16.4

Steps to Reproduce:

1. Sync some repo.
2. Sync it again with no content added.

Actual behavior:
Only one sync audit is created (for the first sync).

Expected behavior:
Audit for each sync should be created.

Business Impact / Additional info: