6.6.2 pyside6-designer fails to run

Upgraded from 6.6.1 to 6.6.2 and now, when attempting to run `pyside6-designer` from command line in pipenv virtual environment:
```

(pysui-gui) fastfrank@~/frankc01/pysui-gui $ pyside6-designer
Traceback (most recent call last):
  File "signature_bootstrap.py", line 77, in bootstrap
  File "signature_bootstrap.py", line 93, in find_incarnated_files
  File "/Users/fastfrank/.pyenv/versions/3.10.6/lib/python3.10/pathlib.py", line 960, in _new_
    self = cls._from_parts(args)
  File "/Users/fastfrank/.pyenv/versions/3.10.6/lib/python3.10/pathlib.py", line 594, in _from_parts
    drv, root, parts = self._parse_args(args)
  File "/Users/fastfrank/.pyenv/versions/3.10.6/lib/python3.10/pathlib.py", line 578, in _parse_args
    a = os.fspath(a)
TypeError: expected str, bytes or os.PathLike object, not NoneType
Fatal Python error: could not initialize part 2
Python runtime state: initialized

Current thread 0x00000001fa907ac0 (most recent call first):
  File "<frozen importlib._bootstrap>", line 241 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 1176 in create_module
  File "<frozen importlib._bootstrap>", line 571 in module_from_spec
  File "<frozen importlib._bootstrap>", line 674 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 1006 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1027 in _find_and_load
  File "<frozen importlib._bootstrap>", line 241 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1078 in _handle_fromlist
  File "/Users/fastfrank/.local/share/virtualenvs/pysui-gui-JP2ByDy9/lib/python3.10/site-packages/PySide6/_init_.py", line 64 in _setupQtDirectories
  File "/Users/fastfrank/.local/share/virtualenvs/pysui-gui-JP2ByDy9/lib/python3.10/site-packages/PySide6/_init_.py", line 124 in <module>
  File "<frozen importlib._bootstrap>", line 241 in _call_with_frames_removed
  File "<frozen importlib._bootstrap_external>", line 883 in exec_module
  File "<frozen importlib._bootstrap>", line 688 in _load_unlocked
  File "<frozen importlib._bootstrap>", line 1006 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1027 in _find_and_load
  File "<frozen importlib._bootstrap>", line 241 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 992 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1027 in _find_and_load
  File "<frozen importlib._bootstrap>", line 241 in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 992 in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1027 in _find_and_load
  File "/Users/fastfrank/.local/share/virtualenvs/pysui-gui-JP2ByDy9/bin/pyside6-designer", line 5 in <module>

Extension modules: xxsubtype (total: 1)
Abort trap: 6
```