Don't show border if useSectionContainer is true

[mud]

Fixes #7841

Checklist

• Includes tests
• Update documentation

Changes proposed in this pull request:

Remove unnecessary border for CardList playground when contained in a Section.

Reviewers should focus on:

I initially opened the issue as a UI bug, but realized CardList does have a bordered prop to control bordering. Personally, I think embedding a CardList as a direct child should remove the border, but I can also understand that these are consumer responsibility.

Screenshot

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• Fix (Fixing an issue with existing functionality)
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Description

Don't show border if useSectionContainer is true

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🐛 Fixes

• Don't show border if useSectionContainer is true (#7848)

[svc-palantir-github]

Don't show border if useSectionContainer is true

Build artifact links for this commit: documentation | landing | table | demo

This is an automated comment from the deploy-preview CircleCI job.

[svc-palantir-github]

Merge branch 'develop' into mud/fix-7841

Build artifact links for this commit: documentation | landing | table | demo

This is an automated comment from the deploy-preview CircleCI job.