9381fcd1

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

Build for aarch64-linux as well as x86_64-linux

Iterate packages and checks over both systems so the tool is available on
aarch64. Switch the overlay to final.callPackage so it builds for the
consumer's system rather than a hard-coded x86_64.
nix-ci-configconfiguredevShelldefaultnix-ci-configx86_64-linux