Fix labels applied to a wrong issue

When "selectedLabels" prop changes,
the watcher for it in labels_select_root.vue
is supposed to update the vuex state "labels".

However, when the sidebar is hidden,
labels_select_root.vue component is destroyed
and the watcher is never used.

Note that we are in the process of deprecating
this particular implemenation of labels dropdown.

Changelog: fixed

app/assets/javascripts/vue_shared/components/sidebar/labels_select_vue/labels_select_root.vue

@@ -173,6 +173,8 @@ export default {
       footerManageLabelTitle: this.footerManageLabelTitle,
     });
 
+    setTimeout(() => this.updateLabelsSetState(), 100);
+
     this.$store.subscribeAction({
       after: this.handleVuexActionDispatch,
     });