Github actions don't support aarch64/ARM64 architecture :(

This is being tracked here: actions/runner-images#2552

This action looks interesting, but fails (predictably) with a message about the image not matching the host: https://github.com/uraimo/run-on-arch-action

A self-hosted runner (i.e. my personal laptop!) would be possible, but can execute arbitrary code, so I'm not going to do that in a public repo like this one. See https://docs.github.com/en/actions/hosting-your-own-runners/adding-self-hosted-runners