Add all available statuses to scope filter for project builds endpoint

What does this MR do?

Adds "skipped" and "created" scopes to project's builds API endpoint (projects/:id/builds?scope=).

Why was this MR needed?

According to documentation the two missing scopes are legitimate options.

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

Closes #26875 (closed)