Added pyproject.toml to lock down dependency versions

[jasonmusespresso]

Summary

• added pyproject.toml file for building the library, following PEP 518;
• added poetry-based dependency management to lock down dependency versions for reproducibility;

Tests

• build successfully at local;

Usage

# install [poetry](https://python-poetry.org/docs/) if not available 
# Linux, macOS, Windows (WSL)
curl -sSL https://install.python-poetry.org | python3 -

# install the dependencies
poetry install

[davidgarciaMontreal]

@jasonmusespresso , Not sure if you could also add the dependency versions for the app demo. As is it's currently broken after this version/pull request: gradio-app/gradio#5498