title: Laravel Queue. Execute a function when the queue becomes empty
body: <p>I have a queue. After completing all the tasks, I would like to execute the function. Example</p>
  <p>Queue:
  Task1
  Task2
  Task3
  Task4
  Task5</p>
  <p>Here, when queue is empty, we have to run Function.
  The documentation only has an event that fires after every task.</p>