Remove numba dependency

[gmarkall]

EDIT: This now removes the numba dependency, which comes transitively from cuDF.

Original description:

numba-cuda is the NVIDIA-maintained CUDA target for Numba, which depends on the numba package.

This PR replaces the numba dependency with numba-cuda. However, similar to @bdice's comment in #648, I don't know if we strictly need this here any more due to the cudf dependency (from rapidsai/cudf#16474) ensuring numba-cuda is present.

[bdice]

I think we can delete the dependencies that come transitively from RAPIDS repositories. Let’s remove the numba pins here.

[gmarkall]

@bdice Many thanks for the suggestion - I think I've implemented it as you suggested (and updated the title / description)

[bdice]

@gmarkall I think this might be ready to merge if you agree. I merged the upstream since CI was failing.

[gmarkall]

@bdice I think this should be fine as the dependency comes from cudf (and will come from its numba-cuda dependency once https://github.com/rapidsai/cudf/pull/16474 is merged).

[bdice]

I updated this PR and retargeted to 24.12. I will give it a /merge so it can move forward if CI passes.

[bdice]

/merge