[VOL-4292] OpenOLT Adapter changes for gRPC migration

Change-Id: I5af2125f2c2f53ffc78c474a94314bba408f8bae
diff --git a/vendor/go.etcd.io/etcd/clientv3/txn.go b/vendor/go.etcd.io/etcd/clientv3/txn.go
index c19715d..c3c2d24 100644
--- a/vendor/go.etcd.io/etcd/clientv3/txn.go
+++ b/vendor/go.etcd.io/etcd/clientv3/txn.go
@@ -18,7 +18,7 @@
 	"context"
 	"sync"
 
-	pb "go.etcd.io/etcd/etcdserver/etcdserverpb"
+	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
 
 	"google.golang.org/grpc"
 )