Moved the build to GitHub actions (#2)

.github/workflows/build.yml

@@ -0,0 +1,41 @@
+name: CI to Docker Hub
+
+on:
+  push:
+    branches: [ master, github-actions ]
+  pull_request:
+    branches: [ master ]
+
+  workflow_dispatch:
+
+jobs:
+  multi:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        repository: [restic-auto]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        
+      - 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.DOCKER_HUB_USERNAME }}
+          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: ${{ matrix.repository }}/
+          file: ${{ matrix.repository }}/Dockerfile
+          platforms: linux/amd64,linux/arm/v6,linux/arm64
+          push: true
+          tags: |
+            ${{ secrets.DOCKER_HUB_USERNAME }}/${{ matrix.repository }}:latest