Fix issue determining StackedBar count

[keithluchtel]

Fixes issue where we weren't properly determining the number of statcked backs from the points data structure.

Description

Fixes #401

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Checklist: (Feel free to delete this section upon completion)

• I have included a changeset if this change will require a version change to one of the packages.
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have run yarn run check:code and all checks pass
• I have created a changeset for new features, patches, or major changes
• I have added tests that prove my fix is effective or that my feature works
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

[changeset-bot]

🦋 Changeset detected

Latest commit: e523b55

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

This PR includes changesets to release 1 package

Name	Type
victory-native	Patch

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Name	Status	Preview	Comments	Updated (UTC)
victory-native-xl-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Oct 23, 2024 4:35pm

[zibs]

🐦‍🔥