Test new feedback component

[DavidBiddle]

What problem does this pull request solve?

Trello card: https://trello.com/c/FtsIrwKY/3107-implement-new-design-system-feedback-banner-and-provide-ds-team-with-analytics

We're testing a new feedback link for the Design System team.

This PR adds a new component for the feedback link and includes it above the footer component.

Things to consider when reviewing

• Ensure that you consider the wider context.
• Does it work when run on your machine?
• Is it clear what the code is doing?
• Do the commit messages explain why the changes were made?
• Are there all the unit tests needed?
• Do the end to end tests need updating before these changes will pass?
• Has all relevant documentation been updated?

[github-actions]

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