Bug fix for physics suites using C3 or SAS convection with MYNN PBL scheme

[lisa-bengtsson]

Issue: ufs-community/ufs-weather-model#2342

When running physics suites using C3 or SAS convection with the prognostic area fraction closure, and MYNN PBL, there is a bug in that the convection expects the field "tendency_of_vertically_diffused_tracer_concentration", to compute the turbulent moisture flux component of the total moisture convergence term, that is output from all PBL schemes except MYNN.

This PR adds "tendency_of_vertically_diffused_tracer_concentration" as output from the MYNN PBL scheme.

[grantfirl]

@lisa-bengtsson For suites using MYNN PBL, I see that GFS_PBL_generic_post is bypassed (where the dvdftra array is copied back to individual terms in the dqdt or (process_split_cumulative_tendency_of_tracers) array). Rather than modify the MYNN scheme to output the needed tendency_of_vertically_diffused_tracer_concentration array, why don't the convective schemes use the process_split_cumulative_tendency_of_specific_humidity variable directly? It looks like C3 is only really after that slice of the larger array anyway.

[lisa-bengtsson]

@lisa-bengtsson For suites using MYNN PBL, I see that GFS_PBL_generic_post is bypassed (where the dvdftra array is copied back to individual terms in the dqdt or (process_split_cumulative_tendency_of_tracers) array). Rather than modify the MYNN scheme to output the needed tendency_of_vertically_diffused_tracer_concentration array, why don't the convective schemes use the process_split_cumulative_tendency_of_specific_humidity variable directly? It looks like C3 is only really after that slice of the larger array anyway.

@grantfirl I don't want to cumulative tendency, I only want the tendency due to PBL processes.

[grantfirl]

@lisa-bengtsson I'm thinking of combining this with #213 to expedite testing/merging. Is that OK with you?

[grantfirl]

@lisa-bengtsson Combined into #223 (Scheduled for UFS merge queue early next week)