Remove unnecessary comment (#620)

* Remove unnecessary comment

on googling 'how to make python file executable', didn't get the expected result. For beginners, it can be time-saving

Author: Praveendwivedi

doc/move_group_python_interface/move_group_python_interface_tutorial.rst

@@ -21,8 +21,7 @@ Open two shells. Start RViz and wait for everything to finish loading in the fir
 
   roslaunch panda_moveit_config demo.launch
 
-Now run the Python code directly in the other shell using ``rosrun``.
-Note in some instances you may need to make the python script executable: ::
+Now run the Python code directly in the other shell using ``rosrun``: ::
 
  rosrun moveit_tutorials move_group_python_interface_tutorial.py