gh-132542: Only run test_native_id_after_fork if native_id is supported (GH-134408)

Author: noamcohen97

Lib/test/test_threading.py

@@ -1353,6 +1353,7 @@ def do_flush(*args, **kwargs):
         assert_python_ok("-c", script)
 
     @skip_unless_reliable_fork
+    @unittest.skipUnless(hasattr(threading, 'get_native_id'), "test needs threading.get_native_id()")
     def test_native_id_after_fork(self):
         script = """if True:
             import threading