python310Packages.caio: Disable failing test

The loop fixture is missing and it is unclear where it should be coming
from.

pkgs/development/python-modules/caio/default.nix

@@ -25,6 +25,11 @@ buildPythonPackage rec {
     pytestCheckHook
   ];
 
+  disabledTests = [
+    # fixture 'loop' not found
+    "test_operations_cancel_cleanly"
+  ];
+
   pythonImportsCheck = [
     "caio"
   ];