fix(TreeView): Fix undefined error

[silvalaura]

Issue: #1518

What I did

• added optional chaining to prevent undefined error
• the issue with max call size stack was because itemIds were not unique, so just an issue with my example
• reformatted a few files, so review this PR while hiding whitespace changed

Screenshots:

N/A

Checklist

• [X] changeset has been added
• [X] Pull request description is descriptive
• [X] I have made corresponding changes to the documentation
• [X] New and existing unit tests pass locally with my changes
• [-] I have added tests that prove my fix is effective or that my feature works

How to test

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🦋 Changeset detected

Latest commit: 06968e85df73c24204481a260abb4011d5b10619

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

| Name | Type | | --------------- | ----- | | react-magma-dom | Patch |

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