ChangeLog false positive for wwn 
### NetBox version

v3.3.2

### Python version

3.8

### Steps to Reproduce

1. Update a Interface
2. Display the generated change log.


### Expected Behavior

Only changed properties are detected as changed.

### Observed Behavior

`wwn` is detected as a changed from `null` to `""`
diff --git a/netbox/dcim/forms/models.py b/netbox/dcim/forms/models.py
index d1d5b1683..a21265db4 100644
--- a/netbox/dcim/forms/models.py
+++ b/netbox/dcim/forms/models.py
@@ -1331,6 +1331,12 @@ class InterfaceForm(InterfaceCommonForm, NetBoxModelForm):
         label='VRF'
     )
 
+    wwn = forms.CharField(
+        empty_value=None,
+        required=False,
+        label='WWN'
+    )
+
     fieldsets = (
         ('Interface', ('device', 'module', 'name', 'type', 'speed', 'duplex', 'label', 'description', 'tags')),
         ('Addressing', ('vrf', 'mac_address', 'wwn')),
['netbox/dcim/forms/models.py']