Use `aptman/qus` instead of `multiarch/qemu-user-static`

[messense]

aptman/qus works on amd64, arm64v8, arm32v7, arm32v6, i386, s390x or ppc64le hosts and supports more architectures.

[messense]

Paves the way for https://github.com/uraimo/run-on-arch-action/issues/28 RISCV 32 and 64 bit support.

[uraimo]

Thanks for the PR @messense but right now I don't see any advantages in migrating to qus other than skipping the user-static installation and supporting non-amd64 host (which we don't need). Both RISC platform should be supported by qemu-user-static too. I'm not merging this for now, if I change my mind I'll recover this PR and will bring it in.

[messense]

I'd like to be able to use this action on self hosted arm64 linux actions runner which is currently not possible.

[triplef]

From this it sounds like one advantage of aptman/qus would be the possibility to avoid installing a full QEMU package and instead only install the necessary archs. Is this something we could do here in order to speed up setup?