remove cleanup of unused set_event_loop_policy

Author: minrk

Lib/test/test_asyncio/test_selector_thread.py

@@ -8,10 +8,6 @@
 from unittest import mock
 
 
-def tearDownModule():
-    asyncio.events._set_event_loop_policy(None)
-
-
 class SelectorThreadTest(unittest.IsolatedAsyncioTestCase):
     async def asyncSetUp(self):
         self._sockets = []