Restore debug print in websocket extensions test for consistency

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: magicmark

tests/test_aiohttp_websocket_subscription.py

@@ -478,6 +478,8 @@ async def test_aiohttp_websocket_subscription_with_extensions(
     async for result in session.subscribe(request):
 
         number = result["number"]
+        print(f"Number received: {number}")
+
         assert number == count
         count -= 1