Fix:remove duplicated CostOverflowingMath trait

[Jiloc]

Description

During the line-by-line diff analysis of the clarity-serialization crate, @fdefelici found out that CostOverflowingMath was not removed from the original clarity crate and ended up being duplicated.

This PR addressed that.

Given that this duplicated symbol slipped through the first two reviews, I did another review do check that ALL symbols in clarity-serialization have no duplicate declaration in clarity. Nothing else was found!

Applicable issues

• fixes #

Additional info (benefits, drawbacks, caveats)

Checklist

• Test coverage for new or modified code paths
• Changelog is updated
• Required documentation changes (e.g., docs/rpc/openapi.yaml and rpc-endpoints.md for v2 endpoints, event-dispatcher.md for new events)
• New clarity functions have corresponding PR in clarity-benchmarking repo
• New integration test(s) added to bitcoin-tests.yml

[fdefelici]

LGMT!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.42%. Comparing base (f61ea59) to head (26afd25).
⚠️ Report is 60 commits behind head on develop.

❌ Your project status has failed because the head coverage (77.42%) is below the target coverage (80.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6480      +/-   ##
===========================================
+ Coverage    71.17%   77.42%   +6.25%     
===========================================
  Files          557      558       +1     
  Lines       341798   342696     +898     
===========================================
+ Hits        243258   265332   +22074     
+ Misses       98540    77364   -21176     

Files with missing lines	Coverage Δ
clarity/src/vm/costs/mod.rs	81.41% <ø> (+2.72%)	⬆️

... and 337 files with indirect coverage changes

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.