Upgrade GitHub Actions workflows

Upgrade GitHub Actions workflows to the latest standard.

Look in .github/workflows/ for test.yml and publish.yml or release.yml.

First make sure they are running the latest versions of e.g. actions/checkout and actions/setup-python.

Consult https://simonw.github.io/actions-latest/versions.txt with curl and grep to find the latest versions.

Next make sure they use current versions of Python in their test matrices. Right now that should be:

["3.10", "3.11", "3.12", "3.13", "3.14"]

Check if the project uses setup.py or pyproject.toml and update any cache keys to reflect that.

Also check if the project uses dependency-groups.dev in pyproject.toml - if it does then any pip install lines in the workflows should use this pattern:

pip install . --group dev

Make sure requires-python is >= 3.10 as well.