message: docs(concat): tidy example
diff: @@ -91,7 +91,7 @@ export function concat<R>(...observables: (ObservableInput<any> | SchedulerLike)
  * import { take } from 'rxjs/operators';
  *
  * const timer = interval(1000).pipe(take(2));
  - * *
  + *
  * concat(timer, timer) // concatenating the same Observable!
  * .subscribe(
  * value => console.log(value),
  