Listener - Send a Custom Email's "${getWorkflowButtons.call()}" method snippet doesn't show Transition button in email notification of issue created from mail handler

When using the Listener - Send a Custom Email, the "${getWorkflowButtons.call()}" method snippet wouldn't show the Transition button in email notification of issue created from mail handler.

Steps to Reproduce

1. Ensure Incoming Mail, Outgoing Mail and Mail Handler are set up in the Jira instance
2. Create a Listener - Send a Custom Email:
   • Events: Issue Created
   • Email template: ${getWorkflowButtons.call()}
   • Email format: HTML
3. Send an email to the Jira Mail Handler
4. Confirm that the Issue from the Mail Handler gets created in Jira
5. Check the notification sent out by the Listener - Send a Custom Email

Expected Behaviour

The mail notification would include the Transition buttons as per set in the Email Template

Actual Behaviour

The mail notification would not include the Transition buttons as per set in the Email Template
This doesn't affect Issues created directly in Jira