[Add] Argument to Support Different Stage

[1chooo]

Related Issue: #5

To support different stages of the product, we can add an argument to deploy various stages. Therefore, the following tasks need to be completed:

• [x] Add ArgumentParser in app.py
• [x] Update Dockerfile to deploy with --prod in the main branch
• [x] Remove the unused docker-compose.yml
• [x] Update the documentation in README.md

[1chooo]

Reference: How to set environment variables in Python?