nixops: containers are incompatible with unstable nixos-container.pl

[adrianparvino]

Describe the bug
NixOps is unable to cat /etc/os-release, stuck at

container0> IP address is 10.233.5.2

To Reproduce
Steps to reproduce the behavior:

1. Create the following NixOps file:

containers.nix

{
  container0 = {
    deployment.targetEnv = "container";
  };
}

2. nixops create -d containers containers.nix
3. nixops deploy -d containers

Expected behavior
NixOps containers should deploy as per 19.09

Metadata
Please run nix run nixpkgs.nix-info -c nix-info -m and paste the result.

• system: "x86_64-linux"
• host os: Linux 4.19.80, NixOS, 20.03.git.3600af2 (Markhor)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.3.1
• channels(root): "nixos-19.09.976.c75de8bc12c"
• nixpkgs: /etc/nixos/nixpkgs

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
# a list of nixos modules affected by the problem
module:

[veprbl]

This probably belongs in https://github.com/NixOS/nixops/issues

[adrianparvino]

To anyone curious who goes through this: You'll need to revert 7cb100b.

[Ma27]

Fixed in ebb6e38 / 7f1ba60