Clear members of GsdPrintNotificationsManager
requested to merge mkasik/gnome-settings-daemon:Clear-members-of-GsdPrintNotificationsManager into master
Clear members of GsdPrintNotificationsManager in stop() to not throw "Cancel-Subscription client-error-not-found" error due to cancelling subscription twice.
This was previously reported here: https://bugzilla.redhat.com/show_bug.cgi?id=2166842