Add indicator that write is complete for every component

[WalterKolczynski-NOAA]

Description

Global workflow needs a method to determine when writing to an output file is complete in order to trigger downstream product generation. The ATM write component touches a small log.fHHH file for this, but other components lack this feature.

Solution

Add a "log" file for each component to indicate when the writing for a forecast hour is complete. Jun suggested using the format log.${component}.fHHH. An issue is already open to track the renaming of the ATM file to include "fv3" (#1635).

Alternatives

Add ecflow triggers.

Related to

Prerequisites:
MOM6:
CICE: NOAA-EMC/CICE#57
WW3: NOAA-EMC/WW3#921
GOCART:
FMS: NOAA-GFDL/FMS#1140

Related:
#1635
NOAA-EMC/global-workflow#935 (This is where the original discussion took place)
NOAA-EMC/global-workflow#1248

[WalterKolczynski-NOAA]

The FMS request was denied, but based on the discussion in the original issue, I don't know that that was actually needed.