Also push the Docker image to the GitHub Container Registry.

.github/workflows/build-image.yml

@@ -62,6 +62,7 @@ jobs:
           if [[ $GITHUB_REF =~ refs/tags/* ]]; then
             TAGS="$TAGS,${{ env.DOCKER_IMAGE_NAME }}:latest"
           fi
+          TAGS="$TAGS,$(echo $TAGS | tr ',' '\n' | sed 's|^|ghcr.io/|' | tr '\n' ',')"
           # Determine the release type.
           if [[ $GITHUB_REF =~ refs/tags/* ]]; then
               IS_RELEASE=yes
@@ -106,6 +107,14 @@ jobs:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_PASSWORD }}
 
+      - name: Login to GitHub Container Registry
+        if: ${{ steps.prep.outputs.is_release == 'yes' }}
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
       - name: Build and push
         uses: docker/build-push-action@v6
         with: