MAINT: Improve specificity of warning check

[bashtage]

• xref REF/Maint: use pandas to_numpy instead of np.asarray #8794
• tests added / passed.
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[bashtage]

xref #8794

Will likely need a helper function to handle casting of pandas ExtensionArrays, if we are to accept them. EIther this, or we reject any array that casts to object in general.

[josef-pkt]

great, thanks

pre is all green except for the bernstein failure.
I want to ignore that one for now. (likely some change in scipy/boost distribution at boundaries that I did not manage to track down)

[bashtage]

See scipy/scipy#18302