Create a clm60cam6LndTuningMode_CPLHIST_ProgCO2 testmod to ensure prognostic CO2 handling happens correctlty

For ALL of our CTSM tests we use diagnostic CO2, which doesn't test prognostic CO2 configurations that are what we actually do when coupled to CAM. When coupled to CAM CO2 is prognostic with _BGC%BPRP in the compset longname. Since, we probably want to test this at the compset level this probably should be done with a new compset, but could also be done with a new testmod. And it might need both.

This comes from this discussion:

https://github.com/ESCOMP/CTSM/pull/4068#issuecomment-4683207819