Bring back some language server rename tests

[odersky]

In #7210 I has to disable some rename tests in the language server test suite. The commit is here:
749932a.

The tests broke after an extensive rewrite of the data structures used for imports. I looked for a while but could not find a problem. It would be good if someone who is more current with the language server found out what exactly is wrong.

[smarter]

Can you point me to the commit with the changes to import ?

[nicolasstucki]

The commit you are looking for is probably bc00dc6