Resolve "404 when trying to create a new issue from the group"

What does this MR do?

Adds a filter with_issues_enabled and with_merge_requests_enabled to the groups/projects API endpoint in order to hide projects with these items disabled on the "Issues" and "Merge Requests" group pages.

This MR is based !11754 (merged)

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

I hope the test case are sufficient, otherwise I can add more.

I am not quite sure, if filtering should happen in find_group_projects or in the GroupProjectsFinder, i preferred find_group_projects here.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
• Conform by the merge request performance guides
• Conform by the style guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them

What are the relevant issue numbers?

Closes #47462 (closed)