Fix numpy VisibleDeprecationWarning for question answering pipeline.
Author: mygithubid1
Pull request: yes

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Fixes #17128 .
`VisibleDeprecationWarning` is addressed by specifying `dtype=object` when creating numpy array. [This post](https://forums.fast.ai/t/visibledeprecationwarning-creating-an-ndarray-from-ragged-nested-sequences-is-deprecated/81774/3), provides a bit more context into what the warning means.


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