Preconditions:

Two admin users exist in application. For example admin and admin2.

Steps:

1. Log in as admin2 and create Content Type
2. Go to edit mode of Content Type from step 1 and log out to lock the CT
3. Log in as admin
4. Remove admin2
5. Go to Content Types and try to edit the admin2's Content Type

Actual result:

if the content type is locked by a user and this user will be deleted, the content type is locked for ever. Notification message: Draft of the Content Type 'New Content Type' already exists and is locked by 'another user'

Expected result:

Lock should be removed after deleting the user.