Bumping released version in go.mod

Change-Id: I9102939f94b43faca58f3a3320da9c8dac26e607
diff --git a/go.mod b/go.mod
index 3a21901..bc41cd5 100644
--- a/go.mod
+++ b/go.mod
@@ -1,4 +1,4 @@
-module github.com/opencord/voltha-protos/v3
+module github.com/opencord/voltha-protos/v4
 
 go 1.13