Realistic setup prep for the Container Registry testing in staging

Problem

We have great improvements with the new Container Registry:

• Use new container registry API for listing repository tags
• ...

That requires a setup with multiple tags/images to be verified in an automated full end-to-end fashion. Currently, we only push one image:tag which is not sufficient for any kind of performance validation on the implementation of the epic above.

Solution

This issue focuses on preparing a project, in staging, with several images and tags to emulate a mid-sized registry scenario and also the automation of this setup. This way we can verify certain functionality that is not really being tested in small push/pull/delete scenarios.

This is targeting the self-managed Container Registry.