Remove container build and deployment

We will continue here with a desktop app. That's now the only artifact.
Maybe containers and deployments will follow later again.

.github/workflows/ci.yml

@@ -53,30 +53,3 @@ jobs:
         run: gleam format --check src test
       - name: Run tests
         run: gleam test
-
-  build-image:
-    name: Build ${{ matrix.env }} container image
-    runs-on: ubuntu-latest
-
-    strategy:
-      matrix:
-        env: [prod, ce]
-
-    steps:
-      - uses: actions/checkout@v4
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
-      - name: Extract metadata (tags, labels) for Docker
-        id: meta
-        uses: docker/metadata-action@v5
-        with:
-          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}-${{ matrix.env }}
-      - name: Build
-        uses: docker/build-push-action@v6
-        with:
-          context: .
-          push: false
-          build-args: |
-            MIX_ENV=${{ matrix.env }}
-          tags: ${{ steps.meta.outputs.tags }}
-          labels: ${{ steps.meta.outputs.labels }}