Fixup various vuejs warnings

dashboard/src/views/EmailMailboxesView.vue

@@ -126,7 +126,9 @@ async function refresh() {
   let tmp = [];
   async function refreshForDomain(domain) {
     let [error, result] = await mailModel.usage(domain);
-    if (error) return console.error(error);
+    // retry if mail addon cannot be reached during restarts
+    if (error && error.status === 424) return setTimeout(refresh, 2000);
+    else if (error) return console.error(error);
 
     const usage = result;
 

dashboard/src/views/EmailStatusView.vue

@@ -2,7 +2,7 @@
 
 import { ref, onMounted } from 'vue';
 import { eachLimit } from 'async';
-import { Button, Icon } from '@cloudron/pankow';
+import { Button } from '@cloudron/pankow';
 import { prettyDecimalSize } from '@cloudron/pankow/utils';
 import Section from '../components/Section.vue';
 import StateLED from '../components/StateLED.vue';