Cleanup github workflows

Took 9 minutes

.github/workflows/docker-build.yml

@@ -0,0 +1,28 @@
+name: Docker build & push
+
+on:
+  push:
+    branches:
+      - master
+    tags:
+      - latest
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
+      - name: build and push
+        if: ${{ env.DOCKER_USERNAME != '' && env.DOCKER_PASSWORD != '' }}
+        env:
+          DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}
+          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
+        run: |
+          ./build.py --push-tags --multiarch