pruneQueue() {
    this.getReadyJobs().forEach(job => {
      const { addedTime, maxAge, failureListeners } = job
      const isJobExpired = (addedTime.getTime() + maxAge) * 1000 < Date.now()

      if (isJobExpired) {
        failureListeners.forEach(listener => {
          listener({
            code: 'JOB_EXPIRED',
            message:
              "This job's age exceeded it's specified maxAge, and was dropped",
          })
        })
      }
    })
  }
Remove "ready" jobs from the queue that have
lived past their max age. Removed jobs have
their failure listeners notified of the same.