desktop: Ensure script session script isn't started twice
Right now, gnome-kiosk provides two modes of starting its script session: 1) systemd 2) directly via gnome-session.
The latter uses a desktop file in /usr/share/applications. Unfortunately that desktop file is getting run in the former case too, because it lacks X-GNOME-HiddenUnderSystemd=true
This commit fixes that.
Closes #6 (closed)