Convert MATLAB-only tests to pyISSM

[lawrenceabird]

There are various CI tests/NightlyRun tests that were originally developed in MATLAB and were not translated to the legacy Python interface. Therefore, these tests were not included in the initial iteration of pyISSM CI tests. These should now be converted to pyISSM to ensure testing parity with MATLAB. For example, the md.model.classes.basalforcings.pico class is not included in any CI tests. Relevant tests for this class include 470-476.

Including these tests will help to ensure the all consistency checks etc. are implemented correctly for all classes.

[justinh2002]

Happy to work on this next week @lawrenceabird while I'm doing a bunch of CI testing stuff — but feel free to assign yourself if you'd like to work on it!

[lawrenceabird]

Knock yourself out @justinh2002! That sounds great, thank you! I think this is a worthwhile task as there have been a few bugs that have crept up in some of these untested classes.

Let me know if you'd like me to review anything!

[lawrenceabird]

@justinh2002 -- to clarify, I was referring only to the nightly run tests here. Those that we skipped in the initial implementation and are tracked in that SharePoint file.