Resolve "Set the language setting to something other than English, the branch of Merge Request will not be visible."

What does this MR do?

The json keys of ref switcher should not be translated.

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

Nothing.

Why was this MR needed?

Set the language setting to something other than English, the branches of Merge Request will not be visible.

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 UX Designer
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
  • Has been reviewed by a Database specialist
• 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
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #48100 (closed)