Storybook: Add BorderRadiusControl story

[Sukhendu2002]

Part of #67165

What?

This PR will add stories for BorderRadiusControl component in the Storybook.

Testing Instructions

1. Run npm run storybook:dev
2. Open the storybook on http://localhost:50240/
3. Check the BorderRadiusControl stories.

Screenshots or screencast

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Co-authored-by: Sukhendu2002 <[email protected]>

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