Add a prebuilt image for aarch64 Linux

[ethanholz]

It would be really cool if we could add support for an aarch64 linux image so you could run this on something like a Raspberry Pi or other ARM platforms. Adding this would probably utilize something like this: https://docs.docker.com/build/ci/github-actions/multi-platform/ . More than happy to submit a PR for how this might look if interested but don't want to make a PR if this is too much of a maintenance burden!