Cleans up mirror capacity if project is a scheduled mirror

Merged Tiago Botelho requested to merge mirror-cleanup-in-project-destroy-service into master

What does this MR do?

If the project was a mirror and was already scheduled (meaning it has capacity reserved for him), we need to cleanup in the event of him being removed. Otherwise that capacity slot will never get released.

Does this MR meet the acceptance criteria?

What are the relevant issue numbers?

Edited by Tiago Botelho