Some of our testmods test things that are default on, rather than the reverse

- deepsoil_bedrock (bedrock is already on except for FATES)
- flexCN_FUN (only opposite is noFUN_flexCN) (turns on flexible-CN/FUN which are default on, but turns LUNA=off which is different)
- rad_hrly_light_res_half (light res already half-degree for Clm60, also iradsw, but already in CamLndTuningMode settings)
- FireLi2016Cru (already default for Clm50)
- FireLi2024CruJra (already default for Clm60)

We should remove the flexCN_FUN testmod and replace it with noFlexCNNoLunaNoFUN. The rad_hrly_light_res_half testmod and test can be removed. The deepsoil_bedrock test could be renamed to deepsoil. The FireLi20* tests should be able to be removed. The ExcessIceStartup_output_sp_exice should stay around as even though it's the default it also turns on the EXCESS_ICE field.

Locate the testmod definitions and associated tests for deepsoil_bedrock, flexCN_FUN, rad_hrly_light_res_half, FireLi2016Cru, FireLi2024CruJra, and ExcessIceStartup_output_sp_exice. Check the documented defaults first, then update or remove the named testmods and tests; done means the intended non-default coverage remains, including EXCESS_ICE output, and the affected tests pass.

Written by the indexing model from the issue text.