Scikit-learn incompatible in stable version

[geislern]

When installing anchor from pypi, scikit-learn 0.24 (current stable release) is installed as a dependency. However, this is incompatible, resulting in 'TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe'' ' when using utils.load_dataset.

Versions 0.22 and 0.23 currently seem to work fine.