cuda.parallel: invoke pytest directly rather than via python -m pytest (#3523)

Co-authored-by: Ashwin Srinath <shwina@users.noreply.github.com>

Author: shwina

ci/test_python.sh

@@ -25,7 +25,7 @@ for module in cuda_parallel cuda_cooperative; do
   begin_group "⚙️ ${module} site-packages"
   pip freeze
   end_group "⚙️ ${module} site-packages"
-  run_command "🚀  Pytest ${module}" python -m pytest -v ./tests
+  run_command "🚀  Pytest ${module}" pytest -v ./tests
   deactivate
 
   popd >/dev/null