chore: support publish beta version to docker

.github/workflows/docker-publish-beta.yml

@@ -0,0 +1,41 @@
+name: 'Docker Publish Beta'
+
+on:
+  push:
+    tags:
+      - 'v*.*.*-*'
+
+jobs:
+  publish:
+    name: Docker Publish Beta
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v2
+      -
+        name: Prepare
+        id: pre
+        run: echo ::set-output name=tag::${GITHUB_REF#refs/tags/v}
+      -
+        name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      -
+        name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      -
+        name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: '.'
+          file: './Dockerfile'
+          platforms: 'linux/amd64,linux/386,linux/arm64,linux/arm/v7'
+          push: true
+          tags: |
+            ttionya/bitwardenrs-backup:${{ steps.pre.outputs.tag }}