Fix issue with isinstance with ArrayLike

[danielward27]

Restricts python version to >3.11 and fixes #230. The tests now run on 3.11 and 3.x to try and avoid further python version related issues. Whilst unfortunate to restrict to >3.11:

• Recent numpyro versions restricts to python > 3.11, and we need a recent numypro version (>=0.20.0), because of recent breaking changes to their distributions, and I will only support the more up to date version.
• This is slightly annoying as numpyro is an optional dependency, but to run all tests on 3.11 and 3.x (some of which include numpyro), this is the easiest (albeit slightly lazy) solution.