docker: GitHub doesn't show labels due to multi-arch image -> add annotation level index

.github/workflows/docker.yml

@@ -48,6 +48,10 @@ jobs:
             type=raw,value=latest,enable={{is_default_branch}}
           labels: |
             org.opencontainers.image.created={{commit_date 'YYYY-MM-DDTHH:mm:ss.SSS[Z]'}}
+        env:
+          # otherwise labels are not shown on GitHub due to multi-arch image: https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-container-registry#adding-a-description-to-multi-arch-images
+          # https://github.com/docker/metadata-action#annotations
+          DOCKER_METADATA_ANNOTATIONS_LEVELS: manifest,index
       -
         name: Login to Docker Hub
         uses: docker/login-action@v3

Dockerfile

@@ -75,28 +75,26 @@ ENV BRANCH=${BRANCH}
 ENV NOW=${NOW}
 
 LABEL org.opencontainers.image.title="free-games-claimer" \
-      # org.opencontainers.image.name="free-games-claimer" \
       org.opencontainers.image.description="Automatically claims free games on the Epic Games Store, Amazon Prime Gaming and GOG" \
       org.opencontainers.image.url="https://github.com/vogler/free-games-claimer" \
       org.opencontainers.image.source="https://github.com/vogler/free-games-claimer"
-      # org.opencontainers.image.revision=${COMMIT} \
+      # org.opencontainers.image.name="free-games-claimer" \
       # org.opencontainers.image.ref.name=${BRANCH} \
       # org.opencontainers.image.base.name="ubuntu:jammy" \
-      # org.opencontainers.image.version="latest"
 
 # Configure VNC via environment variables:
-ENV VNC_PORT 5900
-ENV NOVNC_PORT 6080
+ENV VNC_PORT=5900
+ENV NOVNC_PORT=6080
 EXPOSE 5900
 EXPOSE 6080
 
 # Configure Xvfb via environment variables:
-ENV WIDTH 1920
-ENV HEIGHT 1080
-ENV DEPTH 24
+ENV WIDTH=1920
+ENV HEIGHT=1080
+ENV DEPTH=24
 
 # Show browser instead of running headless
-ENV SHOW 1
+ENV SHOW=1
 
 # Script to setup display server & VNC is always executed.
 ENTRYPOINT ["docker-entrypoint.sh"]