Fix new post->tags transition

refs #6483, closes #6541
- removes unloading of all tags when entering the tags screen. Tags list will now function similarly to the content list where already-loaded tags are visible immediately.

Fixes #6483 because it prevents selectize's data being changed out from underneath it before it's destroyed.

core/client/app/routes/settings/tags.js

@@ -30,8 +30,6 @@ export default AuthenticatedRoute.extend(CurrentUserSettings, PaginationRoute, S
     },
 
     model() {
-        this.store.unloadAll('tag');
-
         return this.loadFirstPage().then(() => {
             return this.store.filter('tag', (tag) => {
                 return !tag.get('isNew');