Add version number to incompatible version message in sao

This merge request include a proposition made by Bob Fern on the Tryton Forum (https://discuss.tryton.org/t/small-improvement-to-sao-how-to-submit-change-request/6258).

It's a simple modification, it's a sort of training for my first merge request on tryton (had to learn how to use hg and the topics extension, it still feels weird coming from git).

Note : I didn't translate the text since it's only a technical information, but did you want me to use gettext also on this ?