Testing on newer Python versions

As of 2023, Python 3.8 was the recommended version to use with xstrm. Python 3.8 is going end of life this year, so will soon be a drag on using this package without updates: My current environment for using xstrm for Colorado Basin drought forecast driver data won't build on 3.8 anymore due to version conflicts. I was able to build successfully on 3.10 (which is also older, but at least has another 2 years of security fixes left) and the workflow runs, though it would be good to have some more formal testing of the package.

Ideally you could have it run on 3.12 or 3.13 (the current active version) for maximum lifespan before the next update.