NEON case won't build: redundant usermod information

[wwieder]

Brief summary of bug

General bug information

NEON case created from scratch failed to build in derecho

ERROR: in validate_variable_value (package Build::Namelist): Variable name fsurdat has exceeded the dimension size of the array.

FWIW, here's the fsurdat file

fsurdat = "$DIN_LOC_ROOT/lnd/clm2/surfdata_map/NEON/surfdata_1x1_NEON_${NEONSITE}_[hist_78pfts_CMIP6_simyr2000_c230601.nc](http://hist_78pfts_cmip6_simyr2000_c230601.nc/)"

CTSM version you are using: [output of git describe]
ctsm5.1.dev176

Does this bug cause significantly incorrect results in the model's science? [Yes / No]
no

Configurations affected:
NEON case created from scratch

Details of bug

./create_newcase --case /glade/derecho/scratch/wwieder/neon_tests/HARV.ad --res CLM_USRDAT --compset I1PtClm51Bgc --output-root /glade/derecho/scratch/wwieder/neon_tests --run-unsupported --user-mods-dir NEON/HARV

It seems removing these lines solves the issue

flanduse_timeseries = ' '   ! This isn't needed for a non transient case, but will be once we start using transient compsets
fsurdat = "$DIN_LOC_ROOT/lnd/clm2/surfdata_map/NEON/surfdata_1x1_NEON_${NEONSITE}_hist_78pfts_CMIP6_simyr2000_c230601.nc"

I'll plan to submit a PR to b4b-dev.

[ekluzek]

I've tried to reproduce this and can't seem to get it to fail for me. I also tried to using bash, and sourcing @wwieder bash startup files. So I'm stumped as to why this isn't working for him. The error also doesn't make sense in this context because it's as if fsurdat in the user_nl_clm is arrayed valued. If it was

fsurdat(1) = "$DIN_LOC_ROOT/lnd/clm2/surfdata_map/NEON/surfdata_1x1_NEON_${NEONSITE}_hist_78pfts_CMIP6_simyr2000_c230601.nc"

it would explain it, but it's not.

I'm also not seeing that the perl version makes a difference here.

[wwieder]

I also started clean (again) was was not able to recreate the error. At the same time, the lines from user_nl_clm removed from usermods_dirs in #2472 are redundant, so I suggest we just keep them in