Fix numpy ragged array error.

[natsukium]

Numpy 1.24.0, released over six months ago, banned the creation of implicit ragged arrays and eliminated aliases like numpy.object.
https://numpy.org/devdocs/release/1.24.0-notes.html#expired-deprecations

This PR follows those changes.

[connortann]

Hi @paulbkoch , may I ask if you'd be happy to take a look at this PR?

The slicer lib is a dependency of shap, and it looks like this issue with ragged arrays may be causing trouble downstream. It doesn't look like there has been a release of slicer for several years, so I thought it would be prudent to ask if the maintainers of interpret are happy to take a look at this PR, given that the lib is under the interpretml org?

[connortann]

On a related note, it would be useful to have the unit tests run on CI. I believe this PR will fix slicer/test_slicer.py::test_slicer_ragged_numpy, which currently fails when run locally.

I could submit a PR to try and get it running on GitHub actions, if there are any maintainers around who could review?

[paulbkoch]

Hi @connortann & @natsukium -- Sure, I can put out a release and can accept a PR to add GitHub actions. Are there any other changes you'd like put into the release?

[connortann]

That's fantastic, great to see the library is still maintained and release-able. I think the main thing is to have the issue above fixed, and ideally all the unit tests passing.

[natsukium]

Thanks!