interop: don't use WithBlock dial option in the client (#4805)
interop: don't use WithBlock dial option in the client (#4805)


stanley-cheung/grpc-go,dfawley/grpc-go,menghanl/grpc-go,grpc/grpc-go,stanley-cheung/grpc-go,dfawley/grpc-go,menghanl/grpc-go,grpc/grpc-go