fix formatting

Author: danton267

tests/integration/test_integration.py

@@ -529,4 +529,4 @@ def my_route_f():
     url = f"{dash_duo.server_url}{app.config.requests_pathname_prefix}_dash_startup_route/{url}"
     response = requests.post(url)
     assert response.status_code == 200
-    assert response.text == "hello"
+    assert response.text == "hello"