Update documentation card of miam dataset

[PierreColombo]

Hi !
Paper has been published at EMNLP.

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[PierreColombo]

Ahahah :D not sur how i broke something by updating the README :D

[albertvillanova]

Thanks for the fix @PierreColombo.

Once a README is modified, our CI runs tests on it, requiring additional quality fixes, so that all READMEs are progressively improved and have some minimal tags/sections/information.

For this specific README file, the additional quality requirements of the CI are: https://github.com/huggingface/datasets/runs/7819924428?check_suite_focus=true

E           The following issues were found for the README at `/home/runner/work/datasets/datasets/datasets/miam/README.md`:
E           -	Section `Additional Information` is missing subsection: `Dataset Curators`.
E           -	Section `Additional Information` is missing subsection: `Contributions`.
E           -	`Additional Information` has an extra subsection: `Benchmark Curators`. Skipping further validation checks for this subsection as expected structure is unknown.

[PierreColombo]

Thanks a lot Albert :)))