Update livekit-rtc/tests/test_change_video_quality.py

Co-authored-by: devin-ai-integration[bot] <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Author: cloudwebrtc

livekit-rtc/tests/test_change_video_quality.py

@@ -154,7 +154,8 @@ def _on_event(*args, **kwargs) -> None:
             return
         if predicate is None or predicate(*args, **kwargs):
             fut.set_result(args)
-        room.off(event, _on_event)
+            room.off(event, _on_event)
+
 
     room.on(event, _on_event)
     return fut