Resolve "Add can_create_merge_request_in to Project API response"

What does this MR do?

Expose can? :create_merge_request_in, project to GET /projects/:id API response .

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

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

Closes #198464 (closed)

Required for:

• #35715 (closed)
• #35428 (closed)
• #36232 (closed)
• #36233 (closed)

/cc @rkuba @phikai @dsatcher