Handle chararray deprecation - #19335

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Hmm not sure why the py311 job is failing with No module named 'numpy.char' ...

That is the oldestdeps job. It is grabbing numpy==1.24.0

I think it has to be like this:

>>> from numpy import char
>>> char.array
<function numpy.char.array(obj, itemsize=None, copy=True, unicode=None, order=None)>

Actually seems importing from numpy.char never worked with numpy 1.x : numpy/numpy#27135 (comment)

Yay, finally green devdeps. Thanks! I will approve when the optional CIs finish running.