FSCollector: keep/use given fspath
FSCollector: keep/use given fspath

Via https://github.com/blueyed/pytest/pull/42.

pytest-dev/pytest,markshao/pytest,nicoddemus/pytest,Akasurde/pytest,RonnyPfannschmidt/pytest,The-Compiler/pytest,The-Compiler/pytest,alfredodeza/pytest,nicoddemus/pytest