feat(nix-reuse): Disable the version option

As we are the ones to generate thes REUSE.toml, we control the version

modules/reuse.nix

@@ -23,7 +23,6 @@ let
     attrsOf
     either
     enum
-    int
     listOf
     nullOr
     str
@@ -31,7 +30,7 @@ let
     ;
 
   result = (pkgs.formats.toml { }).generate "REUSE.toml" {
-    inherit (config) version;
+    version = 1;
     annotations = builtins.map (
       {
         path,
@@ -61,14 +60,6 @@ in
       readOnly = true;
     };
 
-    version = mkOption {
-      type = int;
-      default = 1;
-      description = ''
-        Integer value representing the schema version of the `REUSE.toml` file.
-      '';
-    };
-
     defaultLicense = mkOption {
       type = nullOr str;
       default = null;