Workaround for pytest-dev/pytest#1133
Workaround for pytest-dev/pytest#1133

It seems that inside the tox environment `entry.path` points
to the local "pytestqt/logging.py" file (importable from $CWD).
Changing the current directory to "tests" during the tox run
worksaround this problem.

The-Compiler/pytest-qt,pytest-dev/pytest-qt