Fis error in determin if systemd support is present in case of debian 13 and newer.

handle_domain_on_webserver.sh

@@ -133,9 +133,11 @@ fi
 
 # - Is 'systemd' supported on this system
 # -
-if [ "X`which systemd`" = "X" ]; then
-   systemd_exists=false
-else
+systemd_exists=false
+systemd=$(which systemd)
+systemctl=$(which systemctl)
+
+if [[ -n "$systemd" ]] || [[ -n "$systemctl" ]] ; then
    systemd_exists=true
 fi