message: docs: Uses correct component in the `MessageService`
  This commit uses the correct component (`HeroesComponent`) in the.
  `MessageService`. Previously, the `MessageService` was using
  `HeroeService`.
  Closes
  PR Close
diff: @@ -33,7 +33,7 @@ export class HeroesComponent implements OnInit {
  onSelect(hero: Hero): void {
  this.selectedHero = hero;
  - this.messageService.add(`HeroService: Selected hero id=${hero.id}`);
  + this.messageService.add(`HeroesComponent: Selected hero id=${hero.id}`);
  }
  // #docregion getHeroes
  