Issue Summary

Users removed from an instance who still have an Atlassian Account are brought in the /rest/api/2/users/search API endpoint.

Steps to Reproduce

1. Add a user to a Jira instance and create a new issue with that user
2. Completely remove the user from the instance in the User Management
3. Use the /rest/api/2/users/search API endpoint to get all users of the instance

Expected Results

Only current users of the instance should be returned or at least there should be a parameter to turn off this behavior of returning former users. 

Actual Results

Current user and former users with an Atlassian Account are returned.

Workaround

Currently there is no known workaround for this behavior.