fix: Avoid suggestions blink when going to vault tab

In vault tab, we can either see in the suggestion section :
- available suggestions
- no suggestion available with a button to create a login

But we could see a blink because we displayed the section *before* suggestions have been loaded.

So let's display suggestion section only when they have been loaded.

apps/browser/src/vault/popup/components/vault/vault-filter.component.html

@@ -54,7 +54,7 @@ <h1 class="sr-only">{{ "myVault" | i18n }}</h1>
     </ng-container>
   </div>
   <ng-container *ngIf="ciphers && ciphers.length && !showSearching()">
-    <div class="box list" *ngIf="ciphersForCurrentTab.length">
+    <div class="box list" *ngIf="ciphersForCurrentTab && ciphersForCurrentTab.length">
       <h2 class="box-header">
         {{ "suggestions" | i18n }}
       </h2>
@@ -73,7 +73,7 @@ <h2 class="box-header">
         </app-cipher-row>
       </div>
     </div>
-    <div class="box list" *ngIf="!ciphersForCurrentTab.length">
+    <div class="box list" *ngIf="ciphersForCurrentTab && !ciphersForCurrentTab.length">
       <h2 class="box-header">
         {{ "suggestions" | i18n }}
       </h2>