abstractions/X: add another xauth path

Future sddm version will use $XDG_RUNTIME_DIR/xauth_XXXXXX

References:
- https://bugzilla.opensuse.org/show_bug.cgi?id=1174290
- https://bugzilla.suse.com/show_bug.cgi?id=1174293
- https://github.com/sddm/sddm/pull/1230
- https://github.com/jonls/redshift/issues/763

This is the 2.13 version of 35f033ca /
apparmor/apparmor!581

The difference is that this commit avoids using the @{run} variable.

profiles/apparmor.d/abstractions/X

@@ -24,6 +24,7 @@
   owner /{,var/}run/lightdm/*/xauthority r,
   owner /{,var/}run/user/*/gdm/Xauthority r,
   owner /{,var/}run/user/*/X11/Xauthority r,
+  owner /{,var/}run/user/*/xauth_* r,
 
   # the unix socket to use to connect to the display
   /tmp/.X11-unix/* rw,