Express dimensionless units of ice_fraction_xinanjiang and soil_moisture_profile as "1" so UDUNITS2 can parse them (NGWPC-7604)

[PhilMiller]

CFE presently gives units of its input variables ice_fraction_xinanjiang and soil_moisture_profile as the string "none". Both of these are dimensionless fraction quantities. However, the UDUNITS2 library we use to parse units doesn't parse "none" as indicating a dimensionless quantity.

Changes

• Change "none" to "1" so that UDUNITS2 understands it as a dimensionless quantity.

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[cmaynard-ngwpc]

Looks good.