This will also include attic, so we don't need to explicitly do this
in `./bin/nix-build-and-cache` anymore, which is good because that
script gets called a good number of times and doing that repeatedly was
a bit of a waste.
This will allow most Nix users to use the `default` package and without
having to build from source. And also allows any weirdos to get the OCI
image from the Nix binary cache if they want. No idea why that would be
desireable though lol