Decomposition tech note updated for CLM6

[katierocci]

Description of changes

The Decomposition page of the Tech Note has been updated for CLM6 to remove text about the old soil submodel and text has been added for the MIMICS soil submodel. The equations have been updated accordingly.

Specific notes

Contributors other than yourself, if any:

• None

CTSM issues resolved or otherwise addressed, if any:

• Resolves Review 2.22. Decomposition #3868

Requirements before merge:

• I have followed the CTSM contribution guidelines.

[github-actions]

❌ Docs build failed

Build logs

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/home/user/mounted_home/doc/source/tech_note/External_Nitrogen_Cycle/CLM50_Tech_Note_External_Nitrogen_Cycle.rst:25: WARNING: undefined label: 'wiederetal2019' [ref.ref]
/home/user/mounted_home/doc/source/tech_note/FUN/CLM50_Tech_Note_FUN.rst:26: WARNING: undefined label: 'wiederetal2019' [ref.ref]
/home/user/mounted_home/doc/source/tech_note/Introduction/CLM50_Tech_Note_Introduction.rst:58: WARNING: undefined label: 'figure schematic of decomposition model in clm' [ref.numref]
/home/user/mounted_home/doc/source/tech_note/Introduction/CLM50_Tech_Note_Introduction.rst:60: WARNING: undefined label: 'figure pool structure' [ref.numref]
/home/user/mounted_home/doc/source/tech_note/Introduction/CLM50_Tech_Note_Introduction.rst:120: WARNING: undefined label: 'table decomposition rate constants' [ref.numref]
/home/user/mounted_home/doc/source/tech_note/Introduction/CLM50_Tech_Note_Introduction.rst:122: WARNING: undefined label: 'table respiration fractions for litter and som pools' [ref.numref]
Documentation build completed, but with problems that must be resolved.
Re-run with --verbose for full output.

[samsrabin]

The build errors should be resolved now.