Fix #4142: bypass failing diagnostic fields in exact restart tests

[johnpaulalex]

Description of changes

This PR serves as a stopgap measure to restore passing status to the all_outputs integration tests while avoiding permanent, restrictive modifications to the Fortran source code.

Currently, 35 diagnostic fields (originally identified in Issue #3661) fail exact restart checks because they lack proper read/write initialization logic. Instead of commenting these fields out in the core Fortran files (which prevents users from ever outputting them), this PR adds them to the hist_fexcl1 namelist exclusion list specifically within the all_outputs testmod.

Because the all_outputs tests now effectively bypass these broken fields and pass as intended, the ExpectedTestFails.xml override for #3661 has been removed.

(Note: The underlying Fortran restart logic for these fields will be addressed in a follow-up PR, after which this testmod exclusion can be removed, see #4146).

Specific notes

Contributors other than yourself, if any:

• Gemini LLM wrote the fix and this description

CTSM issues resolved or otherwise addressed, if any:

• Resolves Get all_outputs tests working cleanly #4142
• Contributes to FAIL ERP_P64x2_D_Ld3...clm-default--clm-all_outputs COMPARE_base_rest #3661 (as a testing stopgap)

Any user interface changes (namelist or namelist defaults changes)?
Added 35 known-failing diagnostic fields to hist_fexcl1 exclusively inside the cime_config/testdefs/testmods_dirs/clm/all_outputs/user_nl_clm testmod.

Testing planned or performed, if any:

• TODO need to verify that bypassing these fields allows the exact restart test (ERP_P64x2_D_Ld3.f10_f10_mt232.IHistClm60BgcCropCrujra.derecho_gnu.clm-default--clm-all_outputs) to pass.

Requirements before merge:

• I have followed the CTSM contribution guidelines.
• The code in this PR branch builds with no errors.
• The code in this PR branch runs with no errors. Briefly describe tested configuration(s): Exact restart tests (all_outputs).
• This either (a) does not change answers, (b) it only changes answers at roundoff level, or (c) I have performed a scientific evaluation of the answer changes. Which?: (a) does not change answers (only changes which fields are output during the test).
• I have reviewed relevant parts of the CLM documentation Tech Note or User's Guide to determine if anything needs to be changed or added.
• This PR either (a) does not create a need to update the documentation or (b) includes required documentation updates. Which?: (a) does not create a need to update the documentation.

[ekluzek]

Hey @johnpaulalex we already have a different fix that went onto b4b-dev and about to come into master that does this in a different way. See #4136 and #4140.

So I'll close this as a wontdo.

[ekluzek]

Closing because we have a different solution for doing this.