[ FIX ]: Optimize Dockerfile for Layer Caching

[senthil-athiban]

Current Behaviour

The current Dockerfile can be optimized to leverage Docker's layer caching mechanism, which can significantly reduce build times, especially when dependencies remain unchanged. By rearranging the instructions, we can ensure that dependency installation is cached separately from the application code changes.

Benefits:

• Faster build times: By caching the dependencies layer, subsequent builds will be quicker when code changes are made without modifying dependencies.
• Efficient caching: Docker will only re-run the pip install command if the requirements.txt file changes.

[senthil-athiban]

@codekansas could you please assign me this issue.