Cannot delete test-* certs from iManager even though not assigned to any keystore

After importing a 3rd party server certificate and assigning it to all Identity Server 
cert stores, all the test-* test certificates that were created at install time were no
longer in use. To clean up the Certificates UI, the administrator tried to delete all unused 
certificates, including these test-* certificates. All server certs that were not associated
with any cert store were removed but trying to delete the test-* certs resulted in the following
message appearing on the console:


“Error deleting one or more certificates: Only
custom-created keys are eligible for deletion.”

The test-* certificates are used each time a new device is imported. Although they may not be assigned to a cert store, they should not be deleted. Deleting the certs would result in the failure of any new device to import into the Admin Console.