
The property is named useBodyMarkup, not bannerMarkup. This was causing
markup to be disabled for FDO notifications.
Fixes: cc60ce7f94
("notification: Stop using 'update()' from MessageTray.Notification")
Closes: https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/7495
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3247>