Release container architecture

[nampereira]

We are creating release containers with github actions, which uses only (?) x64 runners. We probably want to support other architectures in the near future (e.g. run release containers on Apple silicon).

Some reference/useful links:
https://www.docker.com/blog/multi-arch-build-and-images-the-simple-way/
https://github.com/marketplace/actions/run-on-architecture
https://github.com/actions/virtual-environments