Update Text.features.stories.tsx to no longer use styled-components

[llastflowers]

Closes https://github.com/github/primer/issues/5638

Changelog

New

Added new CSS module

Changed

Changed Text.features.stories.tsx to no longer use styled-components

Removed

Removed anything associated with styled-components

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)

[github-actions]

size-limit report 📦

Path	Size
packages/react/dist/browser.esm.js	90.2 KB (0%)
packages/react/dist/browser.umd.js	90.38 KB (0%)

[Copilot]

Pull Request Overview

This PR updates the Text component's feature stories to remove dependency on styled-components by migrating from the Box component with sx prop styling to standard CSS modules. The change supports the broader initiative to eliminate styled-components from the codebase.

• Replaces Box component usage with a plain div and CSS module class
• Converts inline sx prop styling to CSS module classes
• Introduces a new CSS module file with equivalent styling using CSS custom properties

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
packages/react/src/Text/Text.features.stories.tsx	Removes Box import and sx prop usage, adds CSS module import and applies classes
packages/react/src/Text/Text.features.stories.module.css	New CSS module defining equivalent styles using CSS custom properties