docs: public void add(String instanceId) {
  		ScheduledFuture task = this.scheduler.scheduleAtFixedRate(
  				new ConsulHeartbeatTask(instanceId), this.configuration
  						.computeHearbeatInterval().toStandardDuration().getMillis());
  		ScheduledFuture previousTask = this.serviceHeartbeats.put(instanceId, task);
  		if (previousTask != null) {
  			previousTask.cancel(true);
  		}
  	}