Add details to the asyncio connection error message

tests/test_asyncio/test_connection.py

@@ -505,7 +505,7 @@ async def test_connection_garbage_collection(request):
     ],
 )
 async def test_connect_error_message(error, expected_message):
-    """Test that the _error_message function formats errors correctly"""
+    """Test that the _error_message function formats errors correctly."""
     conn = Connection()
     error_message = conn._error_message(error)
     assert error_message == expected_message