Builds any compatible image for multiple architectures, using GitHub Actions.
This does not use the Docker Hub "Automated Build", which does not support building for architectures other than i386 and amd64.
Setup your project so that it builds from a Dockerfile. Preferably use a multi-stage build on Alpine Linux, to keep the image as small as posible.
Then copy the build.yml to your project and change the Docker Hub username and repository. Finally create a Access Token in Docker Hub and add it a a secret named DOCKERHUB in your GitHub project.
You should now have a multi-arch Docker image in Docker Hub!