Scala 3 support

[grzegorz-bielski]

Forum thread: https://forum.exercism.org/t/scala-3-support/12117

Blocked by: exercism/scala#836

[github-actions]

Hello. Thanks for opening a PR on Exercism 🙂

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[ErikSchierboom]

This is looking good!

[ErikSchierboom]

Great work! We'll need to synchronize the merging of this PR with the merging of the other PR.

[ErikSchierboom]

@grzegorz-bielski When would be a good time for you to merge both PRs?

[grzegorz-bielski]

@ErikSchierboom For me they could be merged at any moment, but I believe I lack proper permissions to do so.

[ErikSchierboom]

Okay, I'll do it tomorrow morning!