enable grpc retry

Change-Id: Id9f1cd18324e2788b2e6c4a9838ffff80ee49f0f
diff --git a/vendor/modules.txt b/vendor/modules.txt
index bda7c1d..21f4b7a 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -81,9 +81,12 @@
 # github.com/google/uuid v1.3.0
 github.com/google/uuid
 # 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/hashicorp/go-uuid v1.0.2
 github.com/hashicorp/go-uuid