MDM - $mdm-clear doesn't expunge Golden Record resources

[dzijianc]

Problem statement

In HAPI-FHIR documentation, it is mentioned for $mdm-clear operation:

After the operation is complete, all targeted MDM links are removed from the system, and their related Golden Resources are deleted and expunged from the server.

Actually, the Golden Record resources are not expunged with $mdm-clear. They are updated and marked as deleted (soft deleted).

Steps to Reproduce

1. configure MDM
2. add some resources with types managed by MDM
3. verify Golden Record resources are present with $mdm-query-links or mdm/mdm/query-links
4. call $mdm-clear
5. wait for batch job to be done

Observed Results

All Golden Record resources were updated and marked as deleted (soft deleted).

Expected Results

All Golden Record resources should have been expunged (hard deleted).