Unable to remove "SNC External" user criteria from catalog items "Not Available For" related list

Build information: Kingston Patch 3

Builds that are known NOT to be affected: N/A
The Environment: Browser(any)

Issue Description: Unable to remove "SNC External" user criteria from catalog items "Not Available For" related list.

On OOB Kingston instance:

1. Install Explicit Roles plugin
2. Open any catalog item
3. Configure > Related Lists
4. Add "Available For" and "Not Available For"
5. Modify something in the Catalog Item and save
6. Notice how the SNC External user criteria gets added to the "Not Available For" related list.
7. Go to the "Available For" related list, click edit, add SNC External and save
8. Go to the "Not Available For" related list, select SNC External and delete.
9. Save the form, notice how the "Not Available For" related list is empty.
10. Make another change to the Catalog Item and save.
11. Notice how SNC External gets added to the "Not Available For" related list.
    
    Customer expects to be able to remove the user criteria from the catalog to be able to create catalog items for CSM or External users. This does not allow them to do so.

The SNC External User criteria is a default user criteria for a catalog item.

The fix for this Problem now allows the deletion of the user criteria if the following condition is met on the instance.

-- To be able to remove this user criteria, the item must contain at least one other user criteria.