Add ignore_submodules to cice

[mathomp4]

This PR adds ignore_submodules: true for CICE in GEOSgcm. This enables a new feature of mepo which should prevent mepo status from showing:

cice6                  | (t) geos/v0.0.2 (DH)
   | icepack: modified, not staged

as well as mepo diff from showing a difference as well. We see this because git sees it since git status and git diff know that icepack was/is a submodule of CICE but we are "ignoring" it and not using it...but git doesn't know that.

So with this change, we can register with mepo that cice should run status and diff ignoring submodule changes.

I'll keep draft for now until I can test and ideally @zhaobin74 can test (since I really don't want to mess up his code). I think it's all good in my testing.

Note if you build locally, you want to get mepo v1.51.1 (or just main) to see this working. I've updated the mepo versions at NCCS and NAS so we should be good...

[zhaobin74]

@mathomp4, this looks good. But I have a question: currently icepack is ignored by cice (our version geos/develop), see. So git status does not show | icepack: modified, not staged. If mepo uses git, why does it see icepack under cice? Thanks,

[mathomp4]

@mathomp4, this looks good. But I have a question: currently icepack is ignored by cice (our version geos/develop), see. So git status does not show | icepack: modified, not staged. If mepo uses git, why does it see icepack under cice? Thanks,

@zhaobin74 The issue is that "internally" git knows there is or was a submodule there...somehow. Not sure how. The .gitmodules file is empty but I know that's not all that git uses for submodules. There are things baked into the .git/ folder stuff that we don't go near. So if you go to cice6 and run git status:

$ git status
HEAD detached at geos/v0.0.2
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
	modified:   icepack (new commits)

Submodules changed but not updated:

* icepack 81a7628...8d80ff5 (1):
  > Merge pull request #1 from GEOS-ESM/bugfix/zhaobin74/recompute-enthalpy

no changes added to commit (use "git add" and/or "git commit -a")

Git knows there is/was a submodule there.

All this really does is when using mepo we can "hide" the fact that git is having issues from the end user. Underneath we would now add --ignore-submodules=all to the call:

$ git status --ignore-submodules=all
HEAD detached at geos/v0.0.2
nothing to commit, working tree clean

[zhaobin74]

Hi @mathomp4, sorry my bad. I used alias git s and forgot --ignore-submodules=all was already built into the alias. Yes, git somehow still remembers icepack, I have a vague memory it happened after I merged with the consortium version.

Anyway, this should go in and make mepo status clean as it should.

Thanks.