Upgrade Yarn to 3.6.4 to fix issue with Node 20.x (part 2)

[clechasseur]

This is part 2 of a fix to upgrade Yarn to 3.6.4 to fix an issue with Node 20.x. The first PR as well as the full explanation is here: #1406

Before this PR is merged, the first PR above needs to be merged. Afterwards, this PR will upgrade Yarn in the remaining exercises.

[github-actions]

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