Fix the invariant message for unimplemented SMT count trailing zeros conversion.

[thomasspriggs]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (74075ec) 79.09% compared to head (7979553) 79.09%.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8044   +/-   ##
========================================
  Coverage    79.09%   79.09%           
========================================
  Files         1699     1699           
  Lines       196512   196512           
========================================
  Hits        155428   155428           
  Misses       41084    41084           

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