chore(FormControl): remove sx props

[francinelucca]

These styles are already in css modules in the applied class https://github.com/primer/react/blob/main/packages/react/src/FormControl/FormControl.module.css#L10-L12

Changelog

Removed

• SX props from FormControl

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

Testing & Reviewing

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github (Learn more about how to run integration tests)

[changeset-bot]

🦋 Changeset detected

Latest commit: 1642708

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

This PR includes changesets to release 1 package

Name	Type
@primer/react	Patch

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[Copilot]

Pull Request Overview

This PR removes inline style props from the FormControl component in favor of CSS class-based styling. The change aims to consolidate styling approaches by removing the display, flexDirection, and alignItems props from the Box component and relying on the classes.ControlVerticalLayout CSS class instead.

• Removes three inline style props (display, flexDirection, alignItems) from the FormControl Box component
• Maintains styling through the existing classes.ControlVerticalLayout CSS class

[github-actions]

👋 Hi, this pull request contains changes to the source code that github/github depends on. If you are GitHub staff, we recommend testing these changes with github/github using the integration workflow. Thanks!

[github-actions]

size-limit report 📦

Path	Size
packages/react/dist/browser.esm.js	92.37 KB (-0.06% 🔽)
packages/react/dist/browser.umd.js	92.49 KB (-0.09% 🔽)

[primer-integration]

👋 Hi from github/github! Your integration PR is ready: https://github.com/github/github/pull/389123

[primer-integration]

🟢 golden-jobs completed with status success.