Use voltha-protos version 4.0.2
Bump major version of voltha-lib-go to 4.0.0 as this change results
in incompatible API version compared to previous version

Change-Id: I1def58361fb1d85f07d6948ebf1ffb7a92eb0d4c
diff --git a/pkg/mocks/kafka/kafka_client.go b/pkg/mocks/kafka/kafka_client.go
index 9d6f50c..268c571 100644
--- a/pkg/mocks/kafka/kafka_client.go
+++ b/pkg/mocks/kafka/kafka_client.go
@@ -21,9 +21,9 @@
 	"sync"
 	"time"
 
-	"github.com/opencord/voltha-lib-go/v3/pkg/kafka"
-	"github.com/opencord/voltha-lib-go/v3/pkg/log"
-	ic "github.com/opencord/voltha-protos/v3/go/inter_container"
+	"github.com/opencord/voltha-lib-go/v4/pkg/kafka"
+	"github.com/opencord/voltha-lib-go/v4/pkg/log"
+	ic "github.com/opencord/voltha-protos/v4/go/inter_container"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 )