Fix/2494 python version review

What is in this MR

fix for #2494

• python packages use pyproject.toml for package description
• python packages are buildable
• black configuration is constrained to py3.9 features and current black version (see black code style stability )
• added Makefile with common commands
• updated dependencies versions docs

- templates are included in baserow as package data in baserow.data.templates, hence they're available with importlib.resources api (moved to #2614)

How to test this MR

• checkout the branch
• remove local venv
• remove web-frontend/node_modules/
• execute make install to create venv from scratch and install BR backend, install frontend deps
  • you can customize venv location by adding VENV_DIR=path/to/venv in your .env file
• execute make build-packages to build wheel files. backend packages are saved in backend/dist/ directory.
• execute make build to create docker images
• execute make lint to run linters on both backend and frontend code
• execute make start to start local dev env
• execute make stop to stop local dev env.
• execute make clean-all to remove venv, node_modules and docker images

- check templates sync with package's entrypoint: - install into venv wheel packages from backend/dist/*.whl - ensure you have proper env vars for backend - ensure backend can access PostgreSQL instance - execute baserow sync_templates to validate templates synchonization (note that baserow is a command available in $PATH after installing BR from a wheel package)

Merge Request Checklist

• changelog.md has been updated if required.
• New/updated Premium/Enterprise features are separated correctly in the premium or enterprise folder
• [ x The latest Chrome and Firefox have been used to test any new frontend features
• Documentation has been updated
• (n/a) Quality Standards are met
• (n/a) Performance: tables are still fast with 100k+ rows, 100+ field tables
• (n/a) The redoc API pages have been updated for any REST API changes
• (n/a) Our custom API docs are updated for changes to endpoints accessed via api tokens
• (n/a) The UI/UX has been updated following UI Style Guide