Test cargo-build-sbf in CI

[LucasSte]

Problem

There was a regression with cargo-build-sbf fixed in #5267 that went undetected because #1581 removed integration tests with cargo-build-sbf.

Summary of Changes

The stable-sbf job now runs sanity tests for cargo-build-sbf.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.3%. Comparing base (39911bb) to head (b5e36c8).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##           master    #5277     +/-   ##
=========================================
- Coverage    83.3%    83.3%   -0.1%     
=========================================
  Files         820      820             
  Lines      371750   371750             
=========================================
- Hits       310025   309963     -62     
- Misses      61725    61787     +62     

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[Lichtso]

This more than doubles the time spent in buildkite/agave/stable-sbf

[LucasSte]

This more than doubles the time spent in buildkite/agave/stable-sbf

I'll avoid rebuilding the x86 test binaries, but cargo-build-sbf needs a place in the CI, so tests times will increase.