Merge pull request #178 from 9seconds/ci-arm32

Build for arm 32 platforms

.github/workflows/ci.yaml

         with:
           pull: true
           context: .
-          platforms: linux/amd64,linux/arm64,linux/386
+          platforms: linux/amd64,linux/arm64,linux/386,linux/arm/v7,linux/arm/v6
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.docker_meta.outputs.tags }}
           labels: ${{ steps.docker_meta.outputs.labels }}