Update action.yml

Author: mcbarton

.github/actions/Emscripten-Notebook-Tests/action.yml

@@ -80,8 +80,6 @@ runs:
         fi
         # Kill the jupyter lite serve process now we are done running xeus-cpp in the
         # Jupyter Lite website.
-        pstree -p $jupyter_lite_process_id
-        kill -9 $jupyter_lite_process_id
-        sleep 10
-        ps
+        pkill -9 timeout
+        pkill -9 jupyter-lite