feat[venom]: optimize branching

[harkal]

What I did

Added a pass to optimize inefficient branches

How I did it

How to verify it

Commit message

This commit introduces a new pass called `BranchOptimizationPass` 
that optimizes inefficient branches.

More specifically, when a branch is led with a logic inversion `ISZERO` 
we remove the `ISZERO` and invert the branch targets.

Description for the changelog

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 94.73684% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 88.63%. Comparing base (96a8384) to head (1f7a792).

:exclamation: Current head 1f7a792 differs from pull request most recent head c329834

Please upload reports for the commit c329834 to get more accurate results.

Files	Patch %	Lines
vyper/venom/passes/branch_optimization.py	94.11%	0 Missing and 1 partial :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4049      +/-   ##
==========================================
- Coverage   91.01%   88.63%   -2.39%     
==========================================
  Files         106      107       +1     
  Lines       15387    15326      -61     
  Branches     3384     3369      -15     
==========================================
- Hits        14005    13584     -421     
- Misses        948     1231     +283     
- Partials      434      511      +77     

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