moving to multi-arch multi-registry Docker

.github/workflows/publish.yml

@@ -0,0 +1,37 @@
+name: publish
+
+on:
+  push:
+    branches:
+      - "main"
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USER }}
+          password: ${{ secrets.DOCKERHUB_PASS }}
+      - name: Login to GitHub Container Registry
+        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@v5
+        with:
+          context: binder
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: |
+            nsidc/tutorials:latest
+            ghcr.io/nsidc/tutorials:latest