Let's refactor commenting out storage-proxy configuration file after the certain pattern

[lizable]

Describe the bug A clear and concise description of what the bug is. 문제가 발생하는 상황에 대한 요약 설명을 적어주세요. Since the new storage host has been added to backend.ai-storage-proxy, it brings ConfigurationError: Validation of agent configuration has failed: ~.

To Reproduce Steps to reproduce the behavior: 문제를 재현하기 위한 순서를 자세히 적어주세요:

1. Go to 'storage-proxy'
2. Run storage-proxy server process by executing the command: python -m ai.backend.storage.server
3. See error.

Expected behavior A clear and concise description of what you expected to happen. 원래 기대했던 동작은 어떤 것인지 명확하게 적어주세요. Executing without configuration error and we need to replace sed_inplace to awk command since it's cumbersome to change every time storage host is added. (please refer this codeblock from backend.ai oneline installation script and sample.toml file from storage-proxy.)

Screenshots If applicable, add screenshots to help explain your problem. Just take a screenshot in your clipboard or copy a picture file and paste it here (Ctrl+V/Cmd+V) so that GitHub automatically attaches and insert it. 가능하다면, 문제 상황을 보여주는 스크린샷을 첨부해주세요. 클립보드에 스크린샷을 찍거나 이미지 파일을 복사해서 여기에 붙여넣으면(Ctrl+V/Cmd+V) GitHub이 자동으로 이곳에 첨부 및 삽입해줍니다.

Client:

• OS: macOS Big Sur 11.6
• App version: [e.g. 19.08.3] (if you are using a GUI client app)
• Browser version: [e.g. Chrome 76, Safari, Edge] (if you are using a GUI web console)
• Python version: 3.9.5
• NodeJS version: [e.g. 12.0] (if you are using the Javascript SDK)

Server:

• OS: macOS Big Sur 11.6
  • Output of uname -a: Darwin iMac 20.6.0 Darwin Kernel Version 20.6.0: Mon Aug 30 06:12:21 PDT 2021; root:xnu-7195.141.6~3/RELEASE_X86_64 x86_64
• Backend.AI version: 21.09.1
• Python version: 3.9.5
• Installation method: used scripts/install-dev.sh

Additional context Add any other context about the problem here. 추가적으로 문제 상황을 설명할 수 있는 다른 맥락을 기술해주세요.