Make repository routes under /-/ scope as default one

What does this MR do?

Make repository routes under /-/ scope as default one. Keep old one for compatibility.

Second attempt for !20455 (merged) but with #118849 (closed) in mind.

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

We already have both scoped and

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers