feat(profile): use desktop user variable in gnome.

Also restrict access to these files.

apparmor.d/groups/gnome/gsd-housekeeping

@@ -34,9 +34,9 @@ profile gsd-housekeeping @{exec_path} flags=(attach_disconnected) {
   /usr/share/gdm/greeter-dconf-defaults r,
   /usr/share/glib-2.0/schemas/gschemas.compiled r,
 
-  /var/lib/gdm{3,}/.config/dconf/user r,
-  /var/lib/gdm{3,}/.local/share/applications/ w,
-  /var/lib/gdm{3,}/greeter-dconf-defaults r,
+  owner@{GDM_HOME}/greeter-dconf-defaults r,
+  owner @{gdm_config_dirs}/dconf/user r,
+  owner @{gdm_share_dirs}/applications/ w,
 
   owner @{user_cache_dirs}/thumbnails/{,**} rw,
   owner @{user_share_dirs}/applications/ rw,