Remove alternate FMS & CRTM versions from unified-dev

[AlexanderRichert-NOAA]

Editing this issue to cover both FMS and CRTM.

FMS and CRTM currently have alternate versions in unified-dev, which, among other things, can trigger concretization bugs. It would be lovely to get to a point where we can see unify: true.

Relatedly:
The following code appears in fms/package.py:

    with when("@release-jcsda"):
        git = "https://github.com/JCSDA/fms.git"

The with when() construct does not function as a conditional statement, so this should be corrected as soon as possible.

[climbfuji]

Regarding 1 - this can be removed.

Regarding 2 - no idea. But with a bit of luck we'll be able to remove the release-jcsda version altogether in the next few weeks to months.

[climbfuji]

@AlexanderRichert-NOAA I don't think we'll be able to avoid multiple CRTM versions for a very long time (until everyone uses CRTM v3 - GFS v18 for the UFS?). For FMS, I am hopeful that once NOAA-GFDL/FMS#1225 is merged, we have the opportunity to remove the different FMS versions and work with the latest FMS release in all our environments.

[climbfuji]

The FMS part of this issue is blocked by NOAA-GFDL/FMS#1225

[climbfuji]

Kicking the can down the road to spack-stack-1.7.0 ...

[climbfuji]

@BenjaminTJohnson We added you here to check what the timeline/prospect of moving to crtm v3 everywhere is. If that's not feasible within the next year or so I suggest with close this issue after the FMS unification is done (hopefully soon!)

[BenjaminTJohnson]

@climbfuji do you mean to ask when we're deprecating v2.x versions and only supporting v3.x?

[climbfuji]

For spack-stack, we need to know when we can stop installing crtm@v2 with each release - probably not for a while because some operational implementations will use crtm@v2?

[BenjaminTJohnson]

@climbfuji yes, my best guess would be 2-3 years before we stop supporting v2.4.0 operationally.

[climbfuji]

We can now remove fms@release-jcsda from the templates and the JEDI packages, and have our package match spack develop. @srherbener Can you take care of this, please?

[climbfuji]

The fms divergence is now history ... all that remains is crtm.