This extends #29053, where it is done for debian/fedora/conda/arch.

https://hub.docker.com/r/nixos/nix/

https://wiki.sagemath.org/Distribution#Nix

To test:

  tox -e docker-nixos-minimal
  tox -e docker-nixos-standard

Depends on #30044

CC: @timokau @dimpase @kliem

Component: build

Author: Matthias Koeppe

Branch/Commit: d4b2af2

Reviewer: Jonathan Kliem

Issue created by migration from https://trac.sagemath.org/ticket/29130