WIP: Improve management of artifacts

What does this MR do?

It adds an artifacts overview page under CI/CD for each project where a user can query artifacts and if he has enough rights he can delete single artifacts or batch delete multiple. (like older than date, or without expiry date)

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

because there is no way to manage artifacts now, if they have no expiry date set (like old artifacts), they need to be deleted by API which is not really user friendly.

The development of this MR is sponsored by @ siemens (/cc @bufferoverflow @koffeinfrei).

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

https://gitlab.com/gitlab-org/gitlab-ce/issues/48862

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