NPM(deps): Bump @wordpress/keycodes from 3.28.0 to 4.15.1

Bumps [@wordpress/keycodes](https://github.com/WordPress/gutenberg/tree/HEAD/packages/keycodes) from 3.28.0 to 4.15.1.
- [Release notes](https://github.com/WordPress/gutenberg/releases)
- [Changelog](https://github.com/WordPress/gutenberg/blob/trunk/packages/keycodes/CHANGELOG.md)
- [Commits](https://github.com/WordPress/gutenberg/commits/@wordpress/[email protected]/packages/keycodes)

---
updated-dependencies:
- dependency-name: "@wordpress/keycodes"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>