Fix failing test in legacy opmath

[astralcai]

A follow up of #6252, does the same but with a different test.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.59%. Comparing base (060bb9a) to head (9e09e84).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #6272   +/-   ##
=======================================
  Coverage   99.59%   99.59%           
=======================================
  Files         444      444           
  Lines       42321    42321           
=======================================
  Hits        42149    42149           
  Misses        172      172           

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