Turn off timeout on PWA update snackbar

aleksis/core/frontend/components/app/App.vue

@@ -187,8 +187,8 @@
       :key="item.id"
       :snackbar-item="item"
     />
-    <v-snackbar v-model="needRefresh" v-if="!refreshDismissed">
-      {{ $t("service_worker.new_version_available") }}
+    <v-snackbar v-model="needRefresh" v-if="!refreshDismissed" timeout="-1">
+      {{ $t("service_worker.new_version_available") }}  
 
       <template #action="{ attrs }">
         <v-btn color="primary" text @click="updateServiceWorker()">