Circular dependency on ClimaCore for test suite

[sriharshakandala]

ClimaTimeSteppers.jl test suite has tests that depend on ClimaCore, creating a circular dependency.

Solution

Move these tests to ClimaCore and eliminate the circular dependency

[sriharshakandala]

cc: @simonbyrne

[charleskawczynski]

There's no circular dependency-- ClimaCore does not depend on ClimaTimeSteppers.jl, and ClimaTimeSteppers.jl does not depend on ClimaCore. The ClimaTimeSteppers test environment depends on both, but that's fine. What's the issue here? Are you getting an error?

[simonbyrne]

it does make it hard to upgrade ClimaComms, as we can't run the ClimaTimeSteppers tests until we've upgraded ClimaCore, and vice versa.

[charleskawczynski]

Would it help if we made ClimaTimeSteppers not depend on ClimaComms? We can (and probably should anyway) undo this patch: 45fa591. Then we can remove the ClimaComms dependency. I'll do that now

[simonbyrne]

We need it for some of the callbacks

[charleskawczynski]

Ah, right

[charleskawczynski]

Would it help if we added a buildkite job in ClimaTimeSteppers that depends on the ClimaCore main branch?

[charleskawczynski]

I suppose we could make ClimaTimeSteppers a lib in ClimaCore. This would make updates easier