test(ui): Convert globalSelectionLink to RTL

[scttcper]

No description provided.

[priscilawebdev]

do you think we can update the file extension to be .tsx?

only the getContext function would need some updates:

  function getContext(query: {project: string[]; environment: string}) {
    return TestStubs.routerContext([
      {
        router: TestStubs.router({
          location: {query},
        }),
      },
    ]);
  }