Request Type field configuration breaks with error after toggling custom field

Issue Summary

Request Type field configuration breaks with error after toggling custom field Required to Optional

Steps to Reproduce

1. Create a custom field, add to a Resolve Issue screen
2. Set field as Required
3. Set field as Optional
4. Navigate to Service Desk Request type settings > Edit fields

Expected Results

The error Cannot Delete a field that is required by Jira or Jira Service Desk

Actual Results

• The following error shows on screen: Cannot Delete a field that is required by Jira or Jira Service Desk
  
• When the request type is used for mail request issue creation, new issues won't be created after the field is toggled

Notes

• Related to JSDSERVER-5782
• Symptom Severity is Major because this bug break creating requests by mail functionality of Service Desk

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available