Makefile: Restore `deps` and `testdeps` (#4060)
Makefile: Restore `deps` and `testdeps` (#4060)


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