feat: give higher priority to pam_sss module

With default priority (128), pam-auth-update put module pam_sss after
module pam_unix in /etc/pam.d/common-auth, and then a user with a
local account and local password synchronized with AD password will
never be granted a Kerberos TGT on session opening.

debian/postrm

@@ -8,6 +8,7 @@ case "$1" in
             dconf update
         fi
     ;;
+
     remove|upgrade|failed-upgrade|abort-install|abort-upgrade|disappear)
     ;;