Upgrade to ESLint v9

[stefcameron]

PR Checklist

Please leave this checklist in your PR.

• Source changes maintain stated browser compatibility.
• Web APIs introduced have deep browser coverage, including Safari (often very late to adopt new APIs).
• Issue being fixed is referenced.
• Unit test coverage added/updated.
• E2E test coverage added/updated.
• Typings added/updated.
• Changes do not break SSR:
  • Careful to test typeof document/window !== 'undefined' before using it in code that gets executed on load.
• README updated (API changes, instructions, etc.).
• Changes to dependencies explained.
• Changeset added (run npm run changeset locally to add one, and follow the prompts).
  • EXCEPTION: A Changeset is not required if the change does not affect any of the source files that produce the package bundle. For example, demo changes, tooling changes, test updates, or a new dev-only dependency to run tests more efficiently should not have a Changeset since it will not affect package consumers.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 86dd0b2

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