Folder in file explorer cannot be expanded (Send unnormalized file paths from the pytest adapter)

[karrtikr]

The extension code expects adapter to return unnormalized file paths, but the adapter is returning after normalizing paths.

This causes a problem in windows. Consider the following file path sent from the adapter.
c:\users\user\documents\test-venv\tests\test_a.py
The actual file path is c:\Users\User\Documents\test-venv\Tests\test_a.py

[ericsnowcurrently]

As noted in #6303 (comment), we still need to be sure to not make unwarranted assumptions in the extension.

[karrtikr]

While validating it, please make sure it fixes issues like #6789 #6554.