Error with numpy 1.24

[jkitchin]

This line params = gryffin.recommend(observations=observations)[0] eventually fails with

AttributeError: module 'numpy' has no attribute 'float'

The issue is np.float was deprecated, and removed (https://numpy.org/devdocs/release/1.24.0-notes.html#expired-deprecations).

It works fine with numpy 1.23.5.

A clumsy fix in a script is: np.float = float.