timeout method
totals with a TimeoutError, if the observable fails to emit a value in the given time span.
- firstspecifies the max duration until the first value must be emitted.
- betweenspecifies the max duration between values (or completion).
- totalspecifies the max duration until completion.
Implementation
Observable<T> timeout({
  Duration? first,
  Duration? between,
  Duration? total,
  Scheduler? scheduler,
}) => TimeoutObservable<T>(
  this,
  first,
  between,
  total,
  scheduler ?? defaultScheduler,
);