nixos/treewide: Move rename.nix imports to their respective modules

A centralized list for these renames is not good because:
- It breaks disabledModules for modules that have a rename defined
- Adding/removing renames for a module means having to find them in the
central file
- Merge conflicts due to multiple people editing the central file

nixos/modules/config/users-groups.nix

@@ -403,6 +403,10 @@ let
       filter types.shellPackage.check shells;
 
 in {
+  imports = [
+    (mkAliasOptionModule [ "users" "extraUsers" ] [ "users" "users" ])
+    (mkAliasOptionModule [ "users" "extraGroups" ] [ "users" "groups" ])
+  ];
 
   ###### interface