Add COM template for JEDI obs (NOAA-EMC#2678)

Adds a COM template to define a path to store obs processed for JEDI.
This will allow UFSDA to stop writing to COM_OBS, which should be
read-only as it belongs to obsproc in operations.

No functional change yet.

parm/config/gfs/config.com

@@ -49,6 +49,8 @@ COM_BASE='${ROTDIR}/${RUN}.${YMD}/${HH}/${MEMDIR}'
 declare -rx COM_TOP_TMPL='${ROTDIR}/${RUN}.${YMD}/${HH}'
 
 declare -rx COM_CONF_TMPL=${COM_BASE}'/conf'
+declare -rx COM_OBS_JEDI=${COM_BASE}'/obs_jedi'
+
 declare -rx COM_ATMOS_INPUT_TMPL=${COM_BASE}'/model_data/atmos/input'
 declare -rx COM_ATMOS_RESTART_TMPL=${COM_BASE}'/model_data/atmos/restart'
 declare -rx COM_ATMOS_ANALYSIS_TMPL=${COM_BASE}'/analysis/atmos'