docs: add JSDoc to deprecate Alert in favor of BannerAlert #6904

[Libens-bufo]

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Description

Add deprecation JSDoc to deprecated code in Alert.tsx

Screenshots/Recordings

Issue

fixes #6890

Checklist

• There is a related GitHub issue
• Tests are included if applicable
• Any added code is fully documented

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[georgewrmarshall]

LGTM! Thanks for your contribution @Libens-bufo 🙏