message: docs: add missing closing bracket
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diff: @@ -185,7 +185,7 @@ searchHeroes(term: string): Observable {
  let heroesURL = `${this.heroesURL}?${term}`;
  return this.http.jsonp(heroesUrl, 'callback').pipe(
  - catchError(this.handleError('searchHeroes', []) // then handle the error
  + catchError(this.handleError('searchHeroes', [])) // then handle the error
  );
  };
  ```
  