title: Not able to perform change event with autocomplete field in Angular formly
body: <p>I am using autocomplete field, to populate the values. I have used templateOptions.change in expression properties to set value of other field, but i have noticed that change event is called only when the value of autocomplete is deselected. when i am trying to select the value from autocomplete change event is not called.</p>
  <p>I have created a stackblitz link to achieve my requirement, I am noticing that change event only calls after we change the value of autocomplete dropdown, and if it is blank and then we select any value it doesn't call the change event.
  I want to know whether there is an option for onselect of dropdown rather than the change event.
  I tried using the hooks too with the template option but didn't work out, it will be helpful if anyone can assist on this.
  Thank you</p>
  <p>Please find this link: <a href="https://stackblitz.com/edit/angular-bf6g6m-6twrjw" rel="nofollow noreferrer">https://stackblitz.com/edit/angular-bf6g6m-6twrjw</a></p>
  <p>First Step:</p>
  <p>When i select first value from autocomplete dropdown: Observation is no change event is called</p>
  <p><a href="https://i.stack.imgur.com/Z51mm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Z51mm.png" alt="enter image description here" /></a></p>
  <p>Second Step:</p>
  <p>Now when i select the other value from dropdown: Observation is change event is called.</p>
  <p><a href="https://i.stack.imgur.com/g1JhA.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/g1JhA.png" alt="enter image description here" /></a></p>