fix: Allow None as default value for Any type hint

[rmshaffer]

Issue #, if available:
#21

Description of changes:
Allow None as a default value for a parameter with type hint of Any.

Testing done:
Existing test case expanded to cover new functionality.

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 (ce26c13) to head (7803a76).

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #22   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines          339       339           
  Branches       103       103           
=========================================
  Hits           339       339           

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