add a simple contract test for CODES in GHA

[caitlinross]

Just a minimal build for now without all the optional dependencies to ensure backwards compatibility as I make more CMake updates to ROSS. We can add a full build in the future.

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Checklist

• Builds cleanly with -Wall and -Wextra
• CI is green
• Added a changelog fragment under Documentation/dev/, unless the change is invisible to anyone outside the PR (test refactors, internal renames, comment-only tweaks)
• Confirmed nothing in CODES breaks. Build CODES against this branch's installed ROSS
• For new features: blog post on the ROSS website, with link in this PR

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 47.86%. Comparing base (a7f15a7) to head (724f9c7).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #202   +/-   ##
=======================================
  Coverage   47.86%   47.86%           
=======================================
  Files          37       37           
  Lines        4745     4745           
  Branches      857      857           
=======================================
  Hits         2271     2271           
  Misses       2469     2469           
  Partials        5        5           

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