gdk: fix typo in the docs for gdk_drag_context_get_selected_action()
gdk: fix typo in the docs for gdk_drag_context_get_selected_action()

Unity-Technologies/gtk,johne53/MB3Gtk-2,Unity-Technologies/gtk,Distrotech/gtk,Distrotech/gtk,Unity-Technologies/gtk,johne53/MB3Gtk-2,Unity-Technologies/gtk,johne53/MB3Gtk-2,Unity-Technologies/gtk,Distrotech/gtk,Distrotech/gtk,johne53/MB3Gtk-2,johne53/MB3Gtk-2,Distrotech/gtk