Support for Numpy 2.0 and higher

[batuhanfaik]

numpy version is not defined within pyproject.toml therefore installing skops in an environment with numpy>=2 raises the following error:

AttributeError: `np.sctypes` was removed in the NumPy 2.0 release. Access dtypes explicitly instead.

[adrinjalali]

Thanks for the report, will look into it.

[batuhanfaik]

Thanks a lot! @adrinjalali when can we expect a new release?