Fix importlib error in older python introduced in #393

[maclandrol]

In python 3.11 (and I would assume earlier python too), metadata is not an attribute of importlib so instead of

import importlib
importlib.metadata

you have to explicitely do:

import importlib.metadata
importlib.metadata

Thus #393 introduces a bug on py<3.13.

Would it be possible to use a python matrix CI github action to prevent this in the future ?

Also if we python <3.8 is still supported then likely needs to have fallback into importlib-metadata and importlib-resources.

[jeromekelleher]

I've also hit this one: sgkit-dev/vcztools#145

[endrebak]

I have started a run to create wheels and so on now for your version. Thanks

https://github.com/pyranges/pyranges/actions/runs/13858623862