Print payu run error message; Update resource for unit test

[Qian-HuiChen]

This PR fixes two issues:

1. Print error message for payu run in subprocess. Closes Add stdout/stderr logs for failed payu run submission #229.
2. Update the OM2 and OM3 resources for unit tests, since the previous branches are removed in the OM2 and OM3 configs.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.75%. Comparing base (5ba476e) to head (6869a94).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #232      +/-   ##
==========================================
- Coverage   90.06%   89.75%   -0.31%     
==========================================
  Files          22       22              
  Lines        1308     1308              
==========================================
- Hits         1178     1174       -4     
- Misses        130      134       +4     

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[jo-basevi]

Thanks for adding this in! Looks good to me