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[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

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

Additional details and impacted files

```diff @@ 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.