python3Packages.jsonnet: move build logic out of python-packages.nix (#424845)

pkgs/development/python-modules/jsonnet/default.nix

···
+{
+  pkgs,
+  buildPythonPackage,
+  setuptools,
+}:
+
+buildPythonPackage {
+  inherit (pkgs.jsonnet) pname version src;
+  pyproject = true;
+
+  build-system = [ setuptools ];
+
+  pythonImportsCheck = [ "_jsonnet" ];
+
+  meta = {
+    inherit (pkgs.jsonnet.meta)
+      description
+      maintainers
+      license
+      homepage
+      ;
+  };
+}

pkgs/top-level/python-packages.nix

···
 
   jsonmerge = callPackage ../development/python-modules/jsonmerge { };
 
-  jsonnet = buildPythonPackage {
-    inherit (pkgs.jsonnet) name src;
-    format = "setuptools";
-  };
+  jsonnet = callPackage ../development/python-modules/jsonnet { };
 
   jsonpatch = callPackage ../development/python-modules/jsonpatch { };