Update python version + VM version

[eugenethreat]

https://github.com/phillycommunitywireless/docs/blob/main/.readthedocs.yaml

Update to a newer python version + VM

# Required
version: 2
mkdocs:
  configuration: mkdocs.yml

# Set the version of Python and other tools you might need
build:
  os: ubuntu-22.04
  tools:
    python: "3.10"

python:
   install:
   - requirements: requirements.txt