modify username hint

configure_thurvserver.tpl

@@ -290,6 +290,7 @@ var _localLang = {
                                         {if $customfields[0].description}
                                             <span class="field-help-text">
                                                 <div class="alert alert-warning">
+                                                    <i class="fas fa-question-circle"></i>
                                                     {$customfields[0].description|replace:'\n':'<br />'}
                                                 </div>
                                             </span>