rmtree: fix rmtree with broken symlinks on python >= 3.8
After https://github.com/python/cpython/issues/86180 func is os.open ( see the patch: https://github.com/python/cpython/pull/23229/files )
After https://github.com/python/cpython/issues/86180 func is os.open ( see the patch: https://github.com/python/cpython/pull/23229/files )