fix: button toolbar component when no extra buttons

src/app/shared/components/presentationals/button-toolbar-detail/button-toolbar-detail.presentational.ts

@@ -13,6 +13,7 @@ import {
 } from "rxjs";
 import {
   BaseResource,
+  isEmptyArray,
   isNullOrUndefined,
   ObservableUtil,
   RoutesEnum,
@@ -119,7 +120,9 @@ export class ButtonToolbarDetailPresentational<TResourceModel extends BaseResour
       },
     ];
 
-    this.listOriginalButton = [...this.listOriginalButton, ...this.listExtraButtons];
+    if (!isNullOrUndefined(this.listExtraButtons) && !isEmptyArray(this.listExtraButtons)) {
+      this.listOriginalButton = [...this.listOriginalButton, ...this.listExtraButtons];
+    }
     this.listOriginalButton.sort((a, b) => {
       if (a.order === b.order) {
         return 0;