fix: default emulator to None shots

[sesmart]

Issue #, if available:
#1301

Description of changes:

None shots matches default sim, and aws_device as the standard default.

Testing done:

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 (df95926) to head (f184f39).

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #1324   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          171       171           
  Lines        11550     11550           
  Branches      1511      1511           
=========================================
  Hits         11550     11550           

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