To add an automation rule, that will change the status of an issue to “done”, when an approval path is finished, you need to:
1.Go to Project Settings → Automation → Create rule
2.Add a Trigger - Incoming Webhook
Save the webhook URL. It will be needed in the further step.
Click Add component.
Select Then : Add an Action. From the right table, select Transition issue.
As Destination status, select Done
As an actor, select a user that has permission to close an issue.
Add a webhook step to an approval path definition. In our example, a webhook step will be the last step. In the Request field paste the webhook URL. The screen that follows will show like below image.