Update utils.py

Author: johnzhou721

Lib/test/test_asyncio/utils.py

@@ -104,7 +104,7 @@ def run_until(loop, pred, timeout=support.SHORT_TIMEOUT):
         loop.run_until_complete(tasks.sleep(delay))
         delay = max(delay * 2, 1.0)
     else:
-        raise futures.TimeoutError()
+        raise TimeoutError()
 
 
 def run_once(loop):