Use help-url in Checkbox

dashboard/src/components/app/Security.vue

@@ -61,7 +61,7 @@ onMounted(() => {
           <textarea id="cspInput" style="white-space: pre-wrap; font-family: monospace;" v-model="csp" placeholder="default-src 'self'; frame-ancestors 'none';" rows="2"></textarea>
         </FormGroup>
 
-        <Checkbox v-model="hstsPreload" style="display: inline-flex;" :label="$t('app.security.hstsPreload')"/> <sup><a href="https://docs.cloudron.io/apps/#hsts-preload" class="help" target="_blank"><i class="fa fa-question-circle"></i></a></sup>
+        <Checkbox v-model="hstsPreload" style="display: inline-flex;" :label="$t('app.security.hstsPreload')" help-url="https://docs.cloudron.io/apps/#hsts-preload"/>
 
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