Python 3.9.7 no longer supported

[rolyp]

GitHub Actions no longer supports 3.9.7.

• bump Python locally to either 3.9.8 or 3.10.0
  • conda install python=3.9.8 ❌ version not available from current channels
  • conda install python=3.9.10 ❌ found conflicts (thousands of lines of error message)
  • official Python 3.9.8 installer for MacOS ❌ wasn't sure what it installed or where
  • brew install python@3.9 ❌ updates 3.9.7 to 3.9.7_1
  • brew install python@3.9.8 ❌ No available formula or cask with the name
  • brew install python@3.10: already installed and up-to-date
    • poetry doesn't know how to find Python 3.10
  • pyenv install 3.10.0
    • poetry doesn't know how to find Python 3.10
  • pyenv install 3.9.8 ❌ python-build: definition not found: 3.9.8
• update pyproject.toml to 3.9.8
  • poetry install doesn't bump Python version: manually delete .venv folder
  • remove conda bullshit from .zshrc
• bump notebooks to 3.9.8
• bump GitHub Actions .yml file to 3.9.8
• pin jsonschema to 3.2.0 to avoid vega/altair/issues/2496