feat: create images for amd64 and arm64

Author: sgaist

.github/workflows/ci.yml

@@ -105,6 +105,10 @@ jobs:
     - test-git-services
     if: "startsWith(github.ref, 'refs/tags/')"
     steps:
+    - name: Set up QEMU
+      uses: docker/setup-qemu-action@v3
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
     - uses: actions/checkout@v4
       with:
         fetch-depth: 0
@@ -115,6 +119,7 @@ jobs:
     - name: Push images
       uses: SwissDataScienceCenter/renku-actions/[email protected]
       env:
+        PLATFORMS: "linux/amd64,linux/arm64"
         DOCKER_USERNAME: ${{ secrets.RENKU_DOCKER_USERNAME }}
         DOCKER_PASSWORD: ${{ secrets.RENKU_DOCKER_PASSWORD }}
     - name: Update component version