test: adapt unit test

src/app/app.component.spec.ts

@@ -1,3 +1,4 @@
+import { NgxWhatsNewModule } from 'ngx-whats-new';
 import { TestBed, waitForAsync } from '@angular/core/testing';
 import { RouterTestingModule } from '@angular/router/testing';
 import { AppComponent } from './app.component';
@@ -33,6 +34,7 @@ describe('AppComponent', () => {
                 ],
                 imports: [
                     MockModule(MatSnackBarModule),
+                    MockModule(NgxWhatsNewModule),
                     RouterTestingModule,
                     TranslateModule.forRoot(),
                 ],