On applet destroyed go out of configure mode
When an applet gets setDestroyed(true) which is the undoable applet delete which just hides it, if userConfiguring was true, go out of configure mode, as no configure ui should be available when the applet doesn't exists officially anymore and more important when the applet or the containment goes out of destroyed (undo) no configure ui should be there
(cherry picked from commit 8cb3608b)
8cb3608b On applet destroyed go out of configure mode
Co-authored-by: Marco Martin notmart@gmail.com