Remove the CLMCRUJRA2024 option, once the "b" has been in place long enough.

Once #382 is done, and enough time has passed that we don't think it's likely we will need to replicate cases run with the older datasets -- we should remove the older option. We might want to wait at least several months to a year. We also need to consider if we need the original option in the cesm3_0 release. If at all possible we should NOT have it in the release.