build(deps-dev): Bump @embroider/core from 3.5.5 to 4.0.3

Bumps [@embroider/core](https://github.com/embroider-build/embroider/tree/HEAD/packages/core) from 3.5.5 to 4.0.3.
- [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/core)

---
updated-dependencies:
- dependency-name: "@embroider/core"
  dependency-version: 4.0.3
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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Author: dependabot[bot]