Fix testing matrix

[ulgens]

The project declares support for Python >=3.8, <=3.13 but several entries were missing in the test matrix.

[dpranke]

Thanks for the PR! However, I was intentionally only running the oldest supported version and the two newest versions likely to introduce breakages. I don't think it's necessary to test every supported version of Python.

[ulgens]

@dpranke I hear you. I don't have a strong opinion here but considering there isn't any significant cost to test all supported versions and this is the common approach, I'd still recommend adding them.

Feel free to close the PR if there is no chance of a merge 🌻

[dpranke]

That's fair. I don't have a strong opinion here, and as you say, the jobs aren't that costly.

So, I'm okay with landing the ci.yml change, but as per the comments in the other PRs, let's revert the uv.lock change (if we can) and address that separately.

[ulgens]

I removed the commits from the other PRs - not sure why I stacked them in the first place.

[dpranke]

LGTM, thanks!