docs: Update our Styling docs

[mannycarrera4]

Summary

Fixes: #3275

Release Category

Documentation

Release Note

Update our Styling docs to be more prescriptive and organized.

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Checklist

• MDX documentation adheres to Canvas Kit's Documentation Guidelines
• Label ready for review has been added to PR

For the Reviewer

• PR title is short and descriptive
• PR summary describes the change (Fixes/Resolves linked correctly)
• PR Release Notes describes additional information useful to call out in a release message or removed if not applicable
• Breaking Changes provides useful information to upgrade to this code or removed if not applicable

Where Should the Reviewer Start?

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• Code
• Documentation
• Testing
• Codemods

Testing Manually

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[cypress]

Workday/canvas-kit    Run #8897

Run Properties:   Passed #8897  •  5f3673e0d2 ℹ️: Merge 1bc2df91b840ab78f3aa6e9e22898a089c8b6b54 into 20b7745e5d54f5eb81ec3219fa85...

Project	Workday/canvas-kit
Branch Review	mc-base-component
Run status	Passed #8897
Run duration	02m 56s
Commit	5f3673e0d2 ℹ️: Merge 1bc2df91b840ab78f3aa6e9e22898a089c8b6b54 into 20b7745e5d54f5eb81ec3219fa85...
Committer	Manuel Carrera
View all properties for this run ↗︎

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Test results
Failures	0
Flaky	1
Pending	21
Skipped	0
Passing	936
View all changes introduced in this branch ↗︎

UI Coverage  21.38%
Untested elements	1524
Tested elements	412

Accessibility  99.27%
Failed rules	6 critical   5 serious   0 moderate   2 minor
Failed elements	98

[jamesfan]

Left a few suggestions. This PR looks good to me otherwise. 👍

[jamesfan]

I changed the PR Release Category to Documentation.