Some tests where comparing actual with expected paths, without taking into account that paths will be different on Windows. This commit uses `path.resolve()` to convert expected paths to their OS-specific form. PR Close #25671
Related discussion: https://github.com/angular/angular/pull/23576#discussion_r187925949. PR Close #25671
The server no longer has files uploaded to it. Instead it is more accurate to refer to it as dealing with "previews" of PRs.