Refactor affinity tests to use require and assert for better readability and error reporting

[mmorel-35]

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Refactor affinity tests to use require and assert for better readability and error reporting

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Fixes #(issue)

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• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file (make new-changelog) or comment /kind changelog-not-required on this PR.
• Updated the corresponding documentation in site/content/docs/main.

[mmorel-35]

/kind changelog-not-required

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.81%. Comparing base (6447363) to head (00ce103).
Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #9009   +/-   ##
=======================================
  Coverage   59.80%   59.81%           
=======================================
  Files         375      375           
  Lines       41056    41056           
=======================================
+ Hits        24554    24557    +3     
+ Misses      15012    15010    -2     
+ Partials     1490     1489    -1     

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