Resolve "Cleanup PreparedAt background job"

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/120692



Merged-by: Adam Hegyi <ahegyi@gitlab.com>
Approved-by: Amy Qualls <aqualls@gitlab.com>
Approved-by: Mohamed Hamda <mhamda@gitlab.com>
Approved-by: Adam Hegyi <ahegyi@gitlab.com>
Reviewed-by: Mohamed Hamda <mhamda@gitlab.com>
Co-authored-by: Marc Shaw <mshaw@gitlab.com>