[Rock-dev] Best way to present the GUI in the Rock tutorials

[Sylvain Joyeux]

HI reviewed Carina's merge request on the website, about changes she
did to the tutorials (thanks for the work Carina). Among other things,
she modified the GUI integration example in

  https://github.com/charrius/base-doc/blob/b68796a4b4e297e4fcbeffcaf8a376c70cd0f6e4/src/documentation/tutorials/520_virtual_joystick.page

to integrate running and visualization in the same script.

I personally had a problem with that, as