Add GitHub Action to publish multi-arch image

.github/workflows/publish.yml

@@ -0,0 +1,30 @@
+name: Docker publish tagged version
+
+on:
+  push:
+    tags:
+      - 'v[0-9].[0-9]+.[0-9]+'
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+      -
+        name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      -
+        name: Build and push
+        uses: docker/build-push-action@v3
+        with:
+          push: true
+          platforms: linux/amd64,linux/arm64,linux/arm/v6,linux/arm/v7,linux/386,linux/ppc64le,linux/s390x
+          tags: axeleroy/wakeonlan-cron-docker:latest,axeleroy/wakeonlan-cron-docker:${{ github.ref_name }}