feat(BorderRadius token)!: Adding a border radius scale

[LinKCoding]

Overview

PR Checklist

• [ ] Related to designs:
• [ ] Related to JIRA ticket: [ABC-123]
• [ ] I have run this code to verify it works
• [ ] This PR includes unit tests for the code change
• [ ] This PR includes testing instructions tests for the code change
• [ ] The alpha package of this PR is passing end-to-end tests in all relevant Codecademy repositories

Testing Instructions

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PR Links and Envs

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Monolith	Monolith PR	Monolith Env
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