v0.2.2

Ready-made Docker images: docker compose up -d now downloads them instead of building on the server.

Added

• Ready-made Docker images on GitHub Container Registry, published for every release:
  ghcr.io/ivamic/immich-steward-core (amd64, arm64) and
  ghcr.io/ivamic/immich-steward-worker (amd64). docker compose up -d downloads them, so
  the images no longer have to be built on the server; --build still builds them from source.
• STEWARD_VERSION in .env to stay on a particular release.
• THIRD_PARTY_NOTICES.md: licenses of the software inside the images (also in /app of the
  images).

Changed

• Updating is now git pull, docker compose pull and docker compose up -d
  (docs/install.md).

Full changelog: v0.2.1...v0.2.2