dummy-backend

Bumps [docker/setup-buildx-action](https://github.com/docker/setup-buildx-action) from 2 to 3.
- [Release notes](https://github.com/docker/setup-buildx-action/releases)
- [Commits](https://github.com/docker/setup-buildx-action/compare/v2...v3

)

---
updated-dependencies:
- dependency-name: docker/setup-buildx-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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