Add proper Windows-specific unittest decorator

Author: floor-licker

Lib/test/test_getpass.py

@@ -168,6 +168,7 @@ def test_falls_back_to_stdin(self):
 except ImportError:
     msvcrt_available = False
 
+@unittest.skipUnless(sys.platform.startswith("win"), "requires Windows")
 @unittest.skipUnless(msvcrt_available, 'tests require system with msvcrt (Windows)')
 class WinGetpassTest(unittest.TestCase):