feat[smock]: add support for overloaded functions

[smartcontracts]

Description
Fixes a bug where smock would not correctly handle overloaded functions. Let's call this a feature. Yay!

[changeset-bot]

🦋 Changeset detected

Latest commit: 8b762be

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@eth-optimism/smock	Patch

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[codecov-commenter]

Codecov Report

Merging #966 (8b762be) into develop (c84d345) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #966   +/-   ##
========================================
  Coverage    82.21%   82.21%           
========================================
  Files           48       48           
  Lines         1895     1895           
  Branches       303      303           
========================================
  Hits          1558     1558           
  Misses         337      337           

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[ben-chain]

Thanks so much--this LGTM!