Extract Docker configuration to a mixin

lib/nixos/configuration.nix

@@ -9,7 +9,10 @@ let
   username = "opdavies";
 in
 {
-  imports = [ ../../modules/mixins/fonts.nix ];
+  imports = [
+    ../../modules/mixins/docker.nix
+    ../../modules/mixins/fonts.nix
+  ];
 
   nixpkgs.config = {
     allowUnfree = true;
@@ -200,15 +203,6 @@ in
   # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
   system.stateVersion = "22.11"; # Did you read the comment?
 
-  virtualisation.docker = {
-    enable = true;
-
-    autoPrune = {
-      enable = true;
-      dates = "weekly";
-    };
-  };
-
   programs.zsh.enable = true;
   programs.zsh.histSize = 5000;
 

modules/mixins/docker.nix

@@ -0,0 +1,10 @@
+{
+  virtualisation.docker = {
+    enable = true;
+
+    autoPrune = {
+      enable = true;
+      dates = "weekly";
+    };
+  };
+}