Update version to 1.9.0
diff --git a/rpc_util.go b/rpc_util.go
index 0fe501f..6a5a7de 100644
--- a/rpc_util.go
+++ b/rpc_util.go
@@ -500,6 +500,6 @@
 )
 
 // Version is the current grpc version.
-const Version = "1.9.0-dev"
+const Version = "1.9.0"
 
 const grpcUA = "grpc-go/" + Version