Updated redwood theme's default density to 'comfortable'

[artpark]

Summary

What was changed:

The default density for redwood has been updated to 'comfortable'.

Why it was changed:

Consumers could forget the density option, this will ensure something still displays even if they forget it.

Testing

This change was tested using:

• [x] WDIO
• [x] Jest
• [ ] Visual testing (please attach a screenshot or recording)
• [ ] Other (please describe below)
• [ ] No tests are needed

Reviews

In addition to engineering reviews, this PR needs:

• [ ] UX review
• [ ] Accessibility review
• [ ] Functional review

Additional Details

This PR resolves:

UXPLATFORM-XXXX

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