docs(cookbook/graphql): fix lint error

Author: Urigo

public/docs/_examples/heroes-graphql/ts/src/app/hero-search.component.ts

@@ -55,8 +55,7 @@ export class HeroSearchComponent implements OnInit {
             id
             name
           }
-        }
-      `,
+        }`,
       variables: {
         search: this.searchTerms
           .debounceTime(300)        // wait 300ms after each keystroke before considering the term