Update unit of errmsg in metavar.py (and/or metadata_parser.py, ccpp-physics, fv3atm, scm) (4 hours)

[climbfuji]

Description

There is a mismatch between the unit of variable errrmsg in metavar.py and the ccpp-physics/fv3atm/scm repositories (which are using none).

Based on the discussion in the recent CCPP framework developer meetings (08/11/2021 and 08/18/2021), the unit for errmsg should probably be none.

This particular change is part of a broader effort to align units between the dictionary of standard names and the ccpp-physics, fv3atm and scm repositories, see ESCOMP/CCPPStandardNames#19.

Solution

Change unit for errmsg in metavar.py from 1 to none in feature/capgen. Merge this update to main, then remove the workaround in parse_checkers.py that was added in PR #391 for the main branch.

Alternatives (optional)

In case we decide to use a different unit for errmsg, update metavar.py, ccpp prebuild's metadata_parser.py, ccpp-physics, fv3atm, scm. This will be a big change in ccpp-physics, since errmsg is a mandatory variable for every scheme, but it should be straightforward.

Related to (optional)

ESCOMP/CCPPStandardNames#19