formats: Set preferLocalBuild in generate builders

Otherwise, remote builds are used for trivial format conversions.

pkgs/pkgs-lib/formats.nix

@@ -65,6 +65,7 @@ rec {
       nativeBuildInputs = [ jq ];
       value = builtins.toJSON value;
       passAsFile = [ "value" ];
+      preferLocalBuild = true;
     } ''
       jq . "$valuePath"> $out
     '') {};
@@ -77,6 +78,7 @@ rec {
       nativeBuildInputs = [ remarshal ];
       value = builtins.toJSON value;
       passAsFile = [ "value" ];
+      preferLocalBuild = true;
     } ''
       json2yaml "$valuePath" "$out"
     '') {};
@@ -270,6 +272,7 @@ rec {
       nativeBuildInputs = [ remarshal ];
       value = builtins.toJSON value;
       passAsFile = [ "value" ];
+      preferLocalBuild = true;
     } ''
       json2toml "$valuePath" "$out"
     '') {};
@@ -467,6 +470,7 @@ rec {
           value = toConf value;
           passAsFile = [ "value" ];
           nativeBuildInputs = [ elixir ];
+          preferLocalBuild = true;
         } ''
         cp "$valuePath" "$out"
         mix format "$out"
@@ -501,6 +505,7 @@ rec {
                 print(f"{key} = {repr(value)}")
       '';
       passAsFile = [ "value" "pythonGen" ];
+      preferLocalBuild = true;
     } ''
       cat "$valuePath"
       python3 "$pythonGenPath" > $out

pkgs/pkgs-lib/formats/hocon/default.nix

@@ -153,6 +153,7 @@ in
           inherit name;
 
           dontUnpack = true;
+          preferLocalBuild = true;
 
           json = builtins.toJSON finalValue;
           passAsFile = [ "json" ];

pkgs/pkgs-lib/formats/libconfig/default.nix

@@ -85,6 +85,7 @@ in
           inherit name;
 
           dontUnpack = true;
+          preferLocalBuild = true;
 
           json = builtins.toJSON value;
           passAsFile = [ "json" ];