This is a type of Job object that allows you to subscribe to updates to the Job. It is returned
by the JobQueue's add() method. Note that the subscription capability is only supported
if the JobQueueStrategy implements the InspectableJobQueueStrategy interface (e.g.
the SqlJobQueueStrategy does support this).
(options?: JobUpdateOptions) => Observable<JobUpdate<T>>Returns an Observable stream of updates to the Job. Works by polling the current JobQueueStrategy's findOne() method
to obtain updates. If the updates are not subscribed to, then no polling occurs.
Polling interval, timeout and other options may be configured with an options arguments JobUpdateOptions.
Job<T>