docs: Add read-the-docs configuration file.

# Documentation: https://docs.readthedocs.io/en/stable/config-file/

version: 2

build:

  os: "ubuntu-22.04"

  tools:

    python: "3.11"

  jobs:

    pre_build:

      - python3 setup.py egg_info --egg-base docs/

# Build from the docs/ directory with Sphinx

sphinx:

  configuration: docs/conf.py

# Explicitly set the version of Python and its requirements

python:

  install:

    - requirements: requirements.txt