Disable wheel pyi test for unsupported configs
The VTK_DISABLE_PYI_TESTING environment variable will disable the testing of the pyi files in the Python wheels. This is used on Windows for Python 3.7 and earlier.
The VTK_DISABLE_PYI_TESTING environment variable will disable the testing of the pyi files in the Python wheels. This is used on Windows for Python 3.7 and earlier.