Provide runTest for tornado 6.1

Author: jwindgassen

tests/test_standalone.py

@@ -2,7 +2,7 @@
 from pathlib import Path
 
 import pytest
-from tornado.testing import AsyncHTTPTestCase
+from tornado import testing
 
 from jupyter_server_proxy.standalone import _default_address_and_port, make_proxy_app
 
@@ -57,12 +57,14 @@ def make_app(unix_socket: bool, skip_authentication: bool):
     )
 
 
-class TestStandaloneProxyRedirect(AsyncHTTPTestCase):
+class TestStandaloneProxyRedirect(testing.AsyncHTTPTestCase):
     """
     Ensure requests are proxied to the application. We need to disable authentication here,
     as we do not want to be redirected to the JupyterHub Login.
     """
 
+    runTest = None  # Required for Tornado 6.1
+
     def get_app(self):
         return make_app(False, True)
 
@@ -90,7 +92,9 @@ def test_on_prefix(self):
 @pytest.mark.skipif(
     sys.platform == "win32", reason="Unix socket not supported on Windows"
 )
-class TestStandaloneProxyWithUnixSocket(AsyncHTTPTestCase):
+class TestStandaloneProxyWithUnixSocket(testing.AsyncHTTPTestCase):
+    runTest = None  # Required for Tornado 6.1
+
     def get_app(self):
         return make_app(True, True)
 
@@ -104,11 +108,13 @@ def test_with_unix_socket(self):
         assert "X-Proxycontextpath: /some/prefix/" in body
 
 
-class TestStandaloneProxyLogin(AsyncHTTPTestCase):
+class TestStandaloneProxyLogin(testing.AsyncHTTPTestCase):
     """
     Ensure we redirect to JupyterHub login when authentication is enabled
     """
 
+    runTest = None  # Required for Tornado 6.1
+
     def get_app(self):
         return make_app(False, False)