Add CI for Godot SDK

[bfops]

Integrate the Godot SDK (#4920) into our release process and any automated tests into the CI.

[bfops]

there's a private PR for the release portion: https://github.com/clockworklabs/SpacetimeDBPrivate/pull/2919

[bfops]

the public portion (#5021) is blocked on having godot tests

[bfops]

I think Lisandro is adding this himself, so closing this one.