GRPC not support grpc_reflection_v1

[quangson137]

I using grpc to test the call to my grpc server. This test will stuck because grpc_reflection_v1alpha is not supported.

refClient = grpcreflect.NewClient(refCtx, reflectpb.NewServerReflectionClient(cc))

[quangson137]

It should change to:

refClient = grpcreflect.NewClientAuto(refCtx, cc)

[quangson137]

#882
I created a PR to fix this.