Support multi-platform docker builds with qemu

.github/workflows/docker-nightly-earthly.yaml

@@ -24,6 +24,13 @@ jobs:
         run: echo "${{ secrets.GH_CR_PAT }}" | docker login https://ghcr.io -u ${{ github.actor }} --password-stdin
         if: env.GH_CR_PAT != null
 
+      - name: Set up QEMU
+        id: qemu
+        uses: docker/setup-qemu-action@v1
+        with:
+          image: tonistiigi/binfmt:latest
+          platforms: all
+
       - uses: actions/checkout@v3
       - name: Checkout and build
         if: env.GH_CR_PAT != null