Update gitlab pipeline to use scripts from MOM6-examples

[adcroft]

This essentially moves commands from .gitlab-ci.yaml to scripts in MOM6-examples.

• This emphasizes the circular dependence we have for testing: MOM6-examples is the one place that "knows" versions and paths to src repositories and so is where we have to define the build process.
• For now, I've put in place the same Makefiles we were using anyway but we will work towards a library-style approach allowing a mode modular definition of the build process
• The .gitlab-ci.yml is much simpler (one line per test)
• I took the opportunity to fold (tidy) much of the output to avoid defaulting to massive raw logs, e.g. https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/jobs/66390
• I also sped up the end-to-end by about 5 minutes although we are subject to waiting in the queue and a slow lustre file system, and thus still ~1 hr.

[Hallberg-NOAA]

I agree with the script simplification in these updates, and they are passing both the TC testing and the updated pipeline testing at https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/pipelines/13051 .