data: Remove org.gnome.SettingsDaemon.XSettings from session

Starting gsd-xsetting will cause issues for the non-systemd startup when combined with Xwayland on-demand. However, we do not need gsd-xsettings as the gnome-initial-setup session never runs X11 applications.

To avoid issues, simply remove it. The alternative solutions would be a change in mutter such as mutter!1771 (merged)