Merge branch 'rm-493-string' into 'develop'

Remove unused string

See merge request ispconfig/ispconfig3!1150

interface/web/dashboard/lib/lang/it.lng

 <?php
 $wb['welcome_user_txt'] = 'Buongiorno %s';
 $wb['available_modules_txt'] = 'Moduli disponibili';
-$wb['last_login_ip'] = "Ultimo login %s da %s";
 ?>