GEOSadas-5.30.3-M21C-5

This brings in the capability to run M21C on the Milan nodes.

The following are part of the changes:

• GMAOpyobs now from repo (rather than directory): v1.0.6
• AeroML NN now from repo: rt1.0.0-cak_tag0 (same as used in GEOSadas-5.41.1)
• GMAO_Shared: v1.7.2+R21C_v1.0.3

There also a number of changes in the fixture here introduced in PR#299

Anyone using this release to setup M21C or M21C-like experiments should read the following:

https://github.com/GEOS-ESM/GEOSadas/wiki/I.-MERRA%E2%80%9021C

Notice in particular

• This release "packs" various tasks of the ensemble in single SLURM jobs as it used to. These are changes in the AtmEnsConfig file.
• To reproduce results on SLES12 - cascade - make sure to set NX and NY in your file.input (for fvsetup) using the same parameters used in the original cascade run(s).