Clean up in accordance with unofficial nix-linter.

machines/CDServer/configuration.nix

@@ -2,8 +2,6 @@
 # your system.  Help is available in the configuration.nix(5) man page
 # and in the NixOS manual (accessible by running ‘nixos-help’).
 
-{ config, pkgs, ... }:
-
 {
   imports = [
       ./hardware-configuration.nix

machines/CDServer/options.nix

@@ -1,4 +1,4 @@
-{ config, lib, ... }:
+{ lib, ... }:
 
 with lib;