Generate scaffold-service faild fail when there are no dependent libraries

[0x-shanks]

Describe the bug
When executing roche g scaffold-service NAME command, an error is displayed under the following conditions

1. missing github.com/izumin5210/grapi/cmd/grapi-gen-scaffold-service
2. missing github.com/golang/protobuf
3. missing github.com/grpc-ecosystem/grpc-gateway
4. missing github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway/descriptor@v1.8.5

To Reproduce
Steps to reproduce the behavior:
execute roche g scaffold-service NAME

Expected behavior
After initialization, the dependent libraries are listed in go.mod and are ready for go mod download.

[riita10069]

You need to install protobuf in your environment.
Please Look at here.
https://github.com/protocolbuffers/protobuf

As for the other module, roche init enable to that the expected behavior you mentioned.