Fix clm-basic tests

[slevis-lmwg]

Description of changes

The relevant tests are

SMS_Lm1.f10_f10_mg37.I1850Clm50BgcCropCmip6waccm.derecho_gnu.clm-basic
ERS_Ly3.f10_f10_mg37.I1850Clm50BgcCropCmip6.derecho_intel.clm-basic
SMS_Ld2_D_PS.f09_g17.I1850Clm50BgcCropCmip6.derecho_intel.clm-basic_interp

• The tests work when we change them from Clm50 to Clm60.
• This requires changes to some associated hardwired stuff in /cime_config.
• We also want to update cmip6 references to cmip7 DROPPED THIS STEP

Specific notes

Contributors other than yourself, if any:
@ekluzek

CTSM Issues Fixed (include github issue #):
Resolves #2787

Are answers expected to change (and if so in what way)?
No

Any User Interface Changes (namelist or namelist defaults changes)?
No

Does this create a need to change or add documentation? Did you do so?
No

Testing performed, if any:
Manual testing of the relevant tests has passed.

[slevis-lmwg]

So... @ekluzek I will argue against doing the cmip6 --> cmip7 transition in this PR for the following reasons:

1. In the spirit of keeping PRs small (as this one is).
2. I grepped for cmip6 in the code like this:
   git grep -i cmip6 | grep -v ChangeLog | grep -v ChangeSum | grep -v rst
   and found 275 lines of code affected in /bld, /cime_config, /python, /tools, and even /lilac
3. This PR's milestone is cesm_3_0_beta04 due Oct 16; you and I have MANY issues to address until then.
   I think we'd be shooting ourselves in the foot by trying to initiate the transition to cmip7 now.
4. cmip7 is the same as ctsm5.4.0 (am I right?) which is due Feb 28.

UPDATE from 2024/9/30 Stand-up meeting:
@ekluzek and @wwieder agreed with me, so this PR is ready for review.
I submitted aux_clm on derecho on Friday.

[slevis-lmwg]

1. I addressed failures in CREATE_NEWCASE in the next commits.
2. For my sanity, I submitted the clm50 version of this test again
   FAIL SMS_Lm1.f10_f10_mg37.I1850Clm50BgcCropCmip6waccm.derecho_gnu.clm-basic RUN
   and this ctsm_sci test that looks almost identical but appears to have passed in CTSM5.3.0: New raw pft/lai/glc-behavior/soilcolor/fire datasets #2500:
   PASS SMS_Lm1.f19_g17.I1850Clm50BgcCropCmip6waccm.derecho_intel.clm-basic RUN
   Why would they behave differently?
   For some reason the latter has the c13 info that it needs, although the tests only differ in resolution and compiler.

[slevis-lmwg]

Rerunning an aux_clm test that looks like a false failure. Otherwise aux_clm on derecho looks OK. UPDATE: Confirmed.