Update arabic_evals.py: Fix custom arabic tasks [2nd attempt] (#444)
Fix alghafa prompt function by explicitly determining the list of choices based on task_name.
(Not all subsets of AlGhafa Native share same columns)
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Co-authored-by: Clémentine Fourrier <22726840+clefourrier@users.noreply.github.com>
Co-authored-by: Nathan Habib <30601243+NathanHB@users.noreply.github.com>