python3Packages.jupyter-server: disable flaky test_cull_connected globally (#517142)

pkgs/development/python-modules/jupyter-server/default.nix

@@ -103,6 +103,8 @@ buildPythonPackage rec {
     "test_subscribe_websocket"
     # test is presumable broken in sandbox
     "test_authorized_requests"
+    # Fails under load on Hydra; kernel stays in 'starting' state due to a zmq socket error
+    "test_cull_connected"
   ]
   ++ lib.optionals stdenv.hostPlatform.isDarwin [
     # attempts to use trashcan, build env doesn't allow this
@@ -119,8 +121,6 @@ buildPythonPackage rec {
   ++ lib.optionals (stdenv.hostPlatform.isDarwin && stdenv.hostPlatform.isx86_64) [
     # TypeError: the JSON object must be str, bytes or bytearray, not NoneType
     "test_terminal_create_with_cwd"
-    # Fails under load (which causes failure on Hydra)
-    "test_cull_connected"
   ];
 
   disabledTestPaths = [