fix(conf): Use vars for severity names (#1)

pacman-zfs-snapshot.sh

@@ -71,9 +71,9 @@ function split_pkgs_by_importance () {
 
 function set_severity () {
     if [[ "${#important_pkgs_in_transaction[@]}" -ge '1' ]]; then
-        severity='imp'
+        severity="${snaps_important_suffix}"
     else
-        severity='trv'
+        severity="${snaps_trivial_suffix}"
     fi
 }