message: docs: make `HeroService#gerHero()` in `toh-pt5` compatible with TS strict mode
  Fixes
  PR Close
diff: @@ -19,7 +19,9 @@ export class HeroService {
  // #docregion getHero
  getHero(id: number): Observable<Hero> {
  - const hero = HEROES.find(h => h.id === id);
  + // For now, assume that a hero with the specified `id` always exists.
  + // Error handling will be added in the next step of the tutorial.
  + const hero = HEROES.find(h => h.id === id) as Hero;
  this.messageService.add(`HeroService: fetched hero id=${id}`);
  return of(hero);
  }
  