Feature: t8code cubed spherical shell setups

[jmark]

This is a follow-PR to #1900.

It implements two cubed spherical shell setups and uses the latest t8code v2.0.0 v3.0.X release.

Closes #1921

This PR depends on a new patch release by t8code. More specifically, this PR: DLR-AMR/t8code#1296

[github-actions]

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[benegee]

Finally!

t8code's latest patch release v3.0.1 contains @jmark's long desired fix for the cubed sphere.

This is now ready to be reviewed and merged!

[JoshuaLampert]

LGTM! I see that the new baroclinic instability test takes roughly 20 seconds in CI, which is, I think, on the border of being acceptable. We could consider reducing the time span even more, but I would also be fine with the current version as the t8code_part2 job doesn't take so long so far.

[benegee]

Thanks for your help @JoshuaLampert . I would be fine with reducing the runtime. The only argument I can think of is that we would like to reproduce the corresponding p4est test here.

[JoshuaLampert]

The only argument I can think of is that we would like to reproduce the corresponding p4est test here.

Yeah, that makes sense.