Silence warnings on async iterator by properly disconnecting

Author: fselmo

tests/integration/go_ethereum/test_goethereum_ws/test_async_iterator_w3.py

@@ -27,7 +27,10 @@ async def async_w3(start_geth_process_and_yield_port):
     endpoint_uri = f"ws://127.0.0.1:{port}"
     # async iterator pattern
     async for w3 in AsyncWeb3(WebSocketProvider(endpoint_uri, request_timeout=10)):
-        return w3
+        yield w3
+        # we won't be iterating to the next w3 instance, so disconnect explicitly
+        await w3.provider.disconnect()
+        break
 
 
 class TestGoEthereumAsyncWeb3ModuleTest(GoEthereumAsyncWeb3ModuleTest):