feat: Enable pep8-naming ruff rules

[callumforrester]

Fixes #282

Enable pep8-naming ruff rules, enforcing that projects follow convetional pep8 naming styles. See https://peps.python.org/pep-0008

[DiamondJoseph]

Isn't this already done and earlier by the Jinja answer verification?

python-copier-template/copier.yml

Line 8 in 76c187c

{% if not (package_name | regex_search('^[a-zA-Z][a-zA-Z_0-9]+$')) %}

e: spoken IRL, I thought this was just chekcing hat the name of the project was compliant, not that naming within the project was compliant. With that in mind, LGTM