VOL-2776 unit test for StartOmciTestAction

Change-Id: Ib0b560b2ae37fab428b3fc058f282b941c5e237f
diff --git a/rw_core/mocks/adapter.go b/rw_core/mocks/adapter.go
index 63474ef..6a8fb22 100644
--- a/rw_core/mocks/adapter.go
+++ b/rw_core/mocks/adapter.go
@@ -254,3 +254,8 @@
 func (ta *Adapter) Child_device_lost(pDeviceID string, pPortNo uint32, onuID uint32) error { //nolint
 	return nil
 }
+
+// Start_omci_test
+func (ta *Adapter) Start_omci_test(device *voltha.Device, request *voltha.OmciTestRequest) (*voltha.TestResponse, error) { //nolint
+	return nil, nil
+}