Publish ARM Docker Images

What is the problem you are facing?

funkwhael/funkwhale and funkwhale/all-in-one are only available for amd64. They should also be available for 32 and 64 bit ARM so people don't have to build images themselves.

What are the possible drawbacks or issues with the requested changes?

It might be hard or inefficient to convince CI to build images for architectures it isn't running on. It also might not be feasible to test all the architectures on CI, so there might be images shipped with architecture-specific bugs.

Context

There was #568 (closed), bu Docker on ARM has changed a lot since then, and it's now supposed to be as easy as installing https://github.com/docker/buildx#installing and doing https://admantium.medium.com/docker-building-images-for-multiple-architectures-4f142f6dda71