Issue in retrieving groups associated with the notification in list notification schemes API

Issue Summary

Performing a request to the /rest/api/3/notificationscheme endpoint https://developer.atlassian.com/cloud/jira/platform/rest/v3/api-group-issue-notification-schemes/#api-rest-api-3-notificationscheme-get does not return the Group information after adding it to the notification of the scheme. 

Steps to Reproduce

1. Select > Issues.
2. Select Notification schemes to open the notification schemes page.
3. Click on Notifications on the right side.
4. Add a group for the notification.
5. Perform the request to the REST API endpoint using expand=all: 

6. /rest/api/3/notificationscheme?expand=all  

1. The group is not included into the notification list

Expected Results

The group would be included.

Actual Results

The group is not included into the result.

Workaround

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