Description of problem:
When I create a host (e.g. using Hosts -> Register Host), then edit it, go to tab Additional Attributes, don't change anything and submit, the change is show in the audit log:

Comment: N/A -> [empty]
Owner: N/A -> N/A
Owner type: N/A -> User

The last row is not present in sat 6.15.

Version-Release number of selected component (if applicable):
Reproduced on Satellite Stream snap 37.0 (6.15) and Sat 6.14.

How reproducible:
Deterministic

Steps to Reproduce:
1. Register a host to the Satellite
2. Edit that host
3. Got to Additional Attributes tab
4. Do not change anything
5. Submit
6. On the host details, click All Audits

Actual results:
Changes shown as described ^

Expected results:
No changes done, no changes shown