fix(react-subnav): scroll-margin-top style

[thiskevinwang]

🎟️ Asana Task
🔍 Preview Link

Relates to

• https://github.com/hashicorp/react-components/pull/391/files

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Description

This unnests scroll-margin-top styling from the .isSticky class.

Preview usage: https://waypoint-p3qzymh84-hashicorp.vercel.app/commands/logs#usage

PR Checklist 🚀

Items in this checklist may not may not apply to your PR, but please consider each item carefully.

• Add Asana and Preview links above.
• Conduct thorough self-review.
• Add or update tests as appropriate.
• Conduct reasonable cross browser testing for both compatibility and responsive behavior (We have a Sauce Labs account for this, if you don't have access, just ask!).
• Conduct reasonable accessibility review (use the WAS as a guide or an axe browser plugin until we establish more formal checks).
• Identify (in the description above) and document (add Asana tasks on this board) any technical debt that you're aware of, but are not addressing as part of this PR.

[changeset-bot]

🦋 Changeset detected

Latest commit: f4636bc

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

This PR includes changesets to release 1 package

Name	Type
@hashicorp/react-subnav	Patch

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[vercel]

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🔍 Inspect: https://vercel.com/hashicorp/react-components/7D4ibpTVA5PTJd9JTHmgAVha3BnQ
✅ Preview: https://react-components-git-kevin-subnav-scroll-hashicorp.vercel.app

[github-actions]

📦 Canary Packages Published

Latest commit: f4636bc

Published 1 packages

@hashicorp/react-subnav@9.1.4-canary-2021103173547

npm install @hashicorp/react-subnav@canary

[BRKalow]

💯