fix: Delegate branch calculation to correct simulator

[speller26]

Issue #, if available:

Description of changes:

RIght now, branch simulations are always done with StateVectorSimulation; we change this behavior to use the correct simulator implementation. With this, users will be able to plug in any backend to run dynamic circuits by subclassing BaseLocalSimulator and Simulation.

Testing done:

Added extra test for error on branch simulation with no provided simulator

Merge Checklist

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (78b059e) to head (b60cd0a).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #369   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           49        49           
  Lines         4884      4884           
  Branches       561       562    +1     
=========================================
  Hits          4884      4884           

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[AbeCoull]

This is a nice change!