message: fix: Not found text is not used for custom tags
diff: </div>
  </ng-select-virtual-scroll>
  - <div class="ng-select-dropdown" *ngIf="showNoItemsFound() && !addTag">
  + <div class="ng-select-dropdown" *ngIf="showNoItemsFound() && !showAddTag()">
  <div class="ng-option disabled">
  {{notFoundText}}
  </div>
  