fix: Prevent unwanted supertype cast in 'search_sorted'

[ritchie46]

fixes #18096

[codecov]

Codecov Report

Attention: Patch coverage is 90.00000% with 5 lines in your changes missing coverage. Please review.

Project coverage is 80.35%. Comparing base (afd93b2) to head (dd1ae54).
Report is 2 commits behind head on main.

Files	Patch %	Lines
...ars-plan/src/plans/conversion/type_coercion/mod.rs	82.14%	5 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #18143   +/-   ##
=======================================
  Coverage   80.34%   80.35%           
=======================================
  Files        1496     1496           
  Lines      197751   197789   +38     
  Branches     2822     2822           
=======================================
+ Hits       158884   158924   +40     
+ Misses      38345    38343    -2     
  Partials      522      522           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.