Incorrectly interpret unit label "ppt" on tile plots

[dkang2]

Describe the bug
When a variable with unit of ppt being used, VERDI doesn't label it correctly (see attached image). I tested for any other unit labels such as pptV, ppb, and any random unit label such as "dumb", it is displayed correctly. Don't know why just the label "ppt" is different?

To Reproduce
Steps to reproduce the behavior:

1. Use the example file at: /work/MOD3DEV/dkj/Verdi/example_files/HR2DAY_ACONC_CL_NO3_v6a1_intel23.2_2022hd_CRACMM3_12US1_BASE_202207_daytime.nc
2. verdi -f /work/MOD3DEV/dkj/Verdi/example_files/HR2DAY_ACONC_CL_NO3_v6a1_intel23.2_2022hd_CRACMM3_12US1_BASE_202207_daytime.nc

ncdump HR2DAY_ACONC_CL_NO3_v6a1_intel23.2_2022hd_CRACMM3_12US1_BASE_202207_daytime.nc | more
netcdf HR2DAY_ACONC_CL_NO3_v6a1_intel23.2_2022hd_CRACMM3_12US1_BASE_202207_daytime {
dimensions:
TSTEP = UNLIMITED ; // (31 currently)
DATE-TIME = 2 ;
LAY = 1 ;
VAR = 2 ;
ROW = 299 ;
COL = 459 ;
variables:
int TFLAG(TSTEP, VAR, DATE-TIME) ;
TFLAG:units = "<YYYYDDD,HHMMSS>" ;
TFLAG:long_name = "TFLAG " ;
TFLAG:var_desc = "Timestep-valid flags: (1) YYYYDDD or (2) HHMMSS " ;
float CL(TSTEP, LAY, ROW, COL) ;
CL:long_name = "CL " ;
CL:units = "ppt " ;
CL:var_desc = "Daily-average " ;
float NO3(TSTEP, LAY, ROW, COL) ;
NO3:long_name = "NO3 " ;
NO3:units = "ppt " ;
NO3:var_desc = "Daily-average " ;