move ioloop into serverapp

Author: Zsailer

jupyter_server/pytest_plugin.py

@@ -110,7 +110,7 @@ def extension_environ(env_config_path, monkeypatch):
 
 @pytest.fixture
 def configurable_serverapp(
-    environ, http_port, tmp_path, home_dir, data_dir, config_dir, runtime_dir, root_dir
+    environ, http_port, tmp_path, home_dir, data_dir, config_dir, runtime_dir, root_dir, io_loop
 ):
     def serverapp(
         config={},