v5 component refactor: Alert Banner

[HollyJoyPhillips]

As part of the v5 Elements release, each component will be reviewed and refactored to ensure best practice and design system alignment

Specification

• Is new component or existing? Possibly replacing (TBC) 'Snacks'
• Is the component being re-named? Renaming to Alert Banner (TBC)
• Is the component design signed off by product and design?
• Guide to component structure & documentation in storybook
• Link to DS in Figma
• Link to Elements Audit in Figma

Developer Checklist

• Styles alignment between Design System and Elements
• Check design tokens in Figma and implement CSS variable tokens if available for relevant component
• Align with accessibility standards / spec as per above
• If relevant, break down component into Styles Only and React component structures
• Ensure all variants of components are documented as appropriate
• Ensure unit test coverage is adequate for component
• Update documentation in MDX file as per guidelines
• Changelog updated to reflect a single beta version per component ideally

Release Checklist

• Approved PR merged to main
• Design & product review and feedback addressed by developer
• Beta release by product / engineering lead to next beta version

[HollyJoyPhillips]

Waiting on confirmation if it's refactor or new component. Once confirmed will move into 'To Do'