enabling grpc retry

Change-Id: I3e83654980386cca080f5ff5f2168e9b405fee1f
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 8fafeca..a3b5d0a 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -152,9 +152,12 @@
 # github.com/gorilla/websocket v1.4.2
 github.com/gorilla/websocket
 # github.com/grpc-ecosystem/go-grpc-middleware v1.3.0
+## explicit
 github.com/grpc-ecosystem/go-grpc-middleware
+github.com/grpc-ecosystem/go-grpc-middleware/retry
 github.com/grpc-ecosystem/go-grpc-middleware/tags
 github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing
+github.com/grpc-ecosystem/go-grpc-middleware/util/backoffutils
 github.com/grpc-ecosystem/go-grpc-middleware/util/metautils
 # github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0
 github.com/grpc-ecosystem/go-grpc-prometheus