Create dataset loader for thai_exam

[SamuelCahyawijaya]

Dataloader name: thai_exam/thai_exam.py
DataCatalogue: http://seacrowd.github.io/seacrowd-catalogue/card.html?thai_exam

Dataset	thai_exam
Description	ThaiExam is a Thai knowledge benchmarking dataset, consisting of multiple-choice questions from examinations in Thailand. The dataset was originally developed for evaluating Typhoon (Thai LLM). This dataset contains 5 splits corresponding to 5 examinations, including ONET, IC, TGAT, TPAT-1, and A-level with a total of 590 questions.
Subsets	-
Languages	tha
Tasks	Question Answering
License	Apache license 2.0 (apache-2.0)
Homepage	https://huggingface.co/datasets/scb10x/thai_exam
HF URL	https://huggingface.co/datasets/scb10x/thai_exam
Paper URL	https://arxiv.org/abs/2312.13951