New docker build mechanism (#2268)

* New docker build mechanism

.github/workflows/dockerbuild.yml

@@ -0,0 +1,60 @@
+name: Build Image on Commit and Release
+
+on:
+  push:
+    branches:
+      - 'master'
+    tags:
+      - '20*'
+
+env:
+  DOCKERHUB_SLUG: rssbridge/rss-bridge
+  GHCR_SLUG: ghcr.io/rss-bridge/rss-bridge
+
+jobs:
+  bake:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v2.3.4
+      -  
+        name: Docker meta
+        id: docker_meta
+        uses: docker/metadata-action@v3.5.0
+        with:
+          images: |
+            ${{ env.DOCKERHUB_SLUG }}
+            ${{ env.GHCR_SLUG }}
+          tags: |
+            type=raw,value=latest
+            type=ref,event=tag,enable=${{ startsWith(github.ref, 'refs/tags/20') }}
+            type=raw,value=stable,enable=${{ startsWith(github.ref, 'refs/tags/20') }}
+      -
+        name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1.6.0
+      -
+        name: Login to DockerHub
+        uses: docker/login-action@v1.10.0
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      -
+        name: Login to GitHub Container Registry
+        uses: docker/login-action@v1.10.0
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      -
+        name: Build and push
+        uses: docker/bake-action@v1.6.0
+        with:
+          files: |
+            ./docker-bake.hcl
+            ${{ steps.docker_meta.outputs.bake-file }}
+          targets: image-all
+          push: true