pythongh-129158: Fix unwanted trailing whitespace in test_asyncio.test_subprocess (python#129181)

Author: ambv

Lib/test/test_asyncio/test_subprocess.py

@@ -905,7 +905,7 @@ def setUp(self):
             # Force the use of the threaded child watcher
             unix_events.can_use_pidfd = mock.Mock(return_value=False)
             super().setUp()
-        
+
         def tearDown(self):
             unix_events.can_use_pidfd = self._original_can_use_pidfd
             return super().tearDown()