Fix: Set does not update the model within the database

see title

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

controller/nucleus/principalNetworkDomain_test.go

@@ -1000,12 +1000,11 @@ func Test_pndImplementation_Confirm(t *testing.T) {
 				t.Error(err)
 				return
 			}
-			_, err = pnd.ChangeMNE(mne.ID(), ppb.ApiOperation_API_OPERATION_UPDATE, "system/config/hostname", "ceos3000")
+			u, err := pnd.ChangeMNE(mne.ID(), ppb.ApiOperation_API_OPERATION_UPDATE, "system/config/hostname", "ceos3000")
 			if err != nil {
 				t.Error(err)
 				return
 			}
-			u := pnd.PendingChanges()[0]
 			if tt.name != "uncommitted" {
 				if err := pnd.Commit(u); (err != nil) != tt.wantErr {
 					t.Errorf("Confirm() error = %v, wantErr %v", err, tt.wantErr)