Fix `ModelCardData`'s datasets typing #6807

Job	Run time
build-windows (3.8)	5m 27s
build-ubuntu (3.8, Repository only)	1m 34s
build-ubuntu (3.8, Everything else)	3m 17s
build-ubuntu (3.13, Repository only)	1m 47s
build-ubuntu (3.13, Everything else)	3m 12s
build-ubuntu (3.13, lfs)	1m 3s
build-ubuntu (3.8, fastai)	1m 12s
build-ubuntu (3.10, fastai)	53s
build-ubuntu (3.8, tensorflow)	57s
build-ubuntu (3.10, tensorflow)	51s
build-ubuntu (3.8, Python 3.8, torch_1.11)	1m 1s
build-ubuntu (3.12, torch_latest)	51s
	22m 5s

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