Add a step for remapping sea surface salinity restoring

[xylar]

This is used in E3SM runs with data atmospheric forcing.

Checklist

• Developer's Guide has been updated
• API documentation in the Developer's Guide (api.rst) has any new or modified class, method and/or functions listed
• Documentation has been built locally and changes look as expected
• Document (in a comment titled Testing in this PR) any testing that was used to verify the changes

[xylar]

Testing

I ran the IcoswISC240 test cases through files_for_e3sm with this branch. I successfully produced the salinity restoring file:

sss.PHC2_monthlyClimatology.IcoswISC240E3r1.20230821.nc

with the same dimensions, variables and variable attributes as attributes as files produced with @maltrud's csh script at:

/lcrc/group/e3sm/ac.xylar/compass_1.2/chrysalis/e3smv3-meshes/sss_restoring/interpSSS

I visually verified that the salinities from the csh script and this branch look identical for the January data in paraview. (I don't have a quick way to verify that they are bit-for-bit and that seems like overkill anyway.)