fix resolver (#740)

transport/grpc/client.go

@@ -87,7 +87,7 @@ func dial(ctx context.Context, insecure bool, opts ...ClientOption) (*grpc.Clien
 		grpc.WithUnaryInterceptor(UnaryClientInterceptor(options.middleware)),
 	}
 	if options.discoverer != nil {
-		grpc.WithResolvers(discovery.NewBuilder(options.discoverer))
+		grpcOpts = append(grpcOpts, grpc.WithResolvers(discovery.NewBuilder(options.discoverer)))
 	}
 	if insecure {
 		grpcOpts = append(grpcOpts, grpc.WithInsecure())

transport/grpc/resolver/discovery/resolver.go

@@ -70,5 +70,5 @@ func parseAttributes(md map[string]string) *attributes.Attributes {
 	for k, v := range md {
 		pairs = append(pairs, k, v)
 	}
-	return attributes.New(pairs)
+	return attributes.New(pairs...)
 }