Bump @embroider/addon-shim from 1.8.7 to 1.8.9 (#503)

Bumps [@embroider/addon-shim](https://github.com/embroider-build/embroider/tree/HEAD/packages/addon-shim) from 1.8.7 to 1.8.9.
- [Release notes](https://github.com/embroider-build/embroider/releases)
- [Changelog](https://github.com/embroider-build/embroider/blob/main/CHANGELOG.md)
- [Commits](https://github.com/embroider-build/embroider/commits/HEAD/packages/addon-shim)

---
updated-dependencies:
- dependency-name: "@embroider/addon-shim"
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>