Cherry-pick NOAA-EMC#343 from release branch: Allow running from cron…

…tab on Cheyenne, as well as fix workflow generation on Cheyenne (NOAA-EMC#378)

## DESCRIPTION OF CHANGES: 
A fix was applied to the release branch for the Cheyenne workflow and automated testing in NOAA-EMC#343, this PR applies the same to develop.

## TESTS CONDUCTED: 
Workflow built and ran on Cheyenne; the following tests were run and all passed:
 - grid_RRFS_CONUS_13km_ics_FV3GFS_lbcs_FV3GFS_suite_GFS_v15p2
 - grid_RRFS_CONUS_25km_ics_FV3GFS_lbcs_FV3GFS_suite_GFS_v15p2
 - grid_RRFS_CONUS_3km_ics_FV3GFS_lbcs_FV3GFS_suite_GFS_v15p2

## ISSUE (optional): 
Fully resolves NOAA-EMC#326

ush/fill_jinja_template.py

@@ -259,7 +259,7 @@ def main(cla):
     tvars = {}
     for var in template_vars:
 
-        if cfg.get(var) is None:
+        if cfg.get(var, "NULL") == "NULL":
             raise KeyError(f'{var} does not exist in user-supplied settings!')
 
         if not cla.quiet:

ush/launch_FV3LAM_wflow.sh

@@ -91,13 +91,14 @@ expt_name="${EXPT_SUBDIR}"
 #
 #-----------------------------------------------------------------------
 #
-if [ "$MACHINE" != "CHEYENNE" ]; then
-  if [ "$MACHINE" = "ORION" ]; then
-    module load contrib rocoto
-  else
-    module purge
-    module load rocoto
-  fi
+if [ "$MACHINE" = "CHEYENNE" ]; then
+  module use -a /glade/p/ral/jntp/UFS_SRW_app/modules/
+  module load rocoto
+elif [ "$MACHINE" = "ORION" ]; then
+  module load contrib rocoto
+else
+  module purge
+  module load rocoto
 fi
 #
 #-----------------------------------------------------------------------

ush/templates/FV3LAM_wflow.xml

@@ -64,17 +64,17 @@ the "HPSS" type is used for the GET_EXTRN_ICS_TN and GET_EXTRN_LBCS_TN
 tasks; and the "FCST" type is used for the RUN_FCST_TN task.
 -->
 
-{%- if (partition_default != "")  %}
+{%- if partition_default is not none %}
 <!ENTITY RSRV_DEFAULT "<account>&ACCOUNT;</account><queue>&QUEUE_DEFAULT;</queue><partition>{{ partition_default }}</partition>">
 {%- else %}
 <!ENTITY RSRV_DEFAULT "<account>&ACCOUNT;</account><queue>&QUEUE_DEFAULT;</queue>">
 {%- endif %}
-{%- if (partition_hpss != "")  %}
+{%- if partition_hpss is not none %}
 <!ENTITY RSRV_HPSS    "<account>&ACCOUNT;</account><queue>&QUEUE_HPSS;</queue><partition>{{ partition_hpss }}</partition>">
 {%- else %}
 <!ENTITY RSRV_HPSS    "<account>&ACCOUNT;</account><queue>&QUEUE_HPSS;</queue>">
 {%- endif %}
-{%- if (partition_fcst != "")  %}
+{%- if partition_fcst is not none %}
 <!ENTITY RSRV_FCST    "<account>&ACCOUNT;</account><queue>&QUEUE_FCST;</queue><partition>{{ partition_fcst }}</partition>">
 {%- else %}
 <!ENTITY RSRV_FCST    "<account>&ACCOUNT;</account><queue>&QUEUE_FCST;</queue>">