added missing device uuid fields for tests

nucleus/principalNetworkDomain_test.go

@@ -36,6 +36,7 @@ func testSetupPnd() {
 
 func mockDevice() Device {
 	return Device{
+		Uuid:      mdid,
 		GoStruct:  nil,
 		SBI:       &OpenConfig{},
 		Transport: &mocks.Transport{},
@@ -375,6 +376,7 @@ func Test_pndImplementation_MarshalDevice(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			pnd := newPnd()
 			d := &Device{
+				Uuid:      tt.args.uuid,
 				GoStruct:  &openconfig.Device{},
 				SBI:       nil,
 				Transport: nil,