fix: multi-dimensional ArrayVar declaration

[rmshaffer]

Issue #, if available:
#13, follow-up to PR #22

Description of changes:
Fix implementation and test for multi-dimensional ArrayVar declaration.

Testing done:
tox passes.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (90c2bbd) to head (4914208).
Report is 13 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #25   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           43        43           
  Lines         1906      1907    +1     
  Branches       320       320           
=========================================
+ Hits          1906      1907    +1     

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[rmshaffer]

@Yash-10 please take a look if you can, this is a quick follow-up to your PR #22.

[Yash-10]

Thanks, @rmshaffer, for these changes and for fixing the small issue from my PR! I think this makes more sense.

[jcjaskula-aws]

LGTM