feat: Add Storybook a11y addon

[smockle]

This PR adds an accessibility-focused Storybook addon:

• Repo: https://github.com/storybookjs/storybook/tree/master/addons/a11y
• Package: https://www.npmjs.com/package/@storybook/addon-a11y

Screenshots

Merge checklist

• Added/updated tests
• Added/updated documentation
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge

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⚠️ No Changeset found

Latest commit: 2397d60

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[colebemis]

Nice! This is awesome ❤️

[khiga8]

Nice ✨