feat: add docker image CD workflow

.github/workflows/docker-image.yml

@@ -0,0 +1,43 @@
+name: Docker Image CD
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Get git tag
+        id: tag
+        uses: dawidd6/action-get-tag@v1
+        with:
+          strip_v: true
+      - 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/[email protected]
+        with:
+          username: ${{ secrets.DOCKER_USER }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Login to GitHub Container Registry
+        uses: docker/[email protected]
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ github.token }}
+      - name: Build and push the docker image
+        uses: docker/build-push-action@v3
+        with:
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: |
+            timothyye/knockd:latest
+            timothyye/knockd:${{steps.tag.outputs.tag}}
+            ghcr.io/timothyye/knockd:latest
+            ghcr.io/timothyye/knockd:${{steps.tag.outputs.tag}}
+          build-args: |
+            VERSION=v${{ steps.tag.outputs.tag }}