python3Packages.python-mapnik: remove superfluous stdenv parameter to buildPythonApplication

Passing `stdenv` directly to `buildPythonPackage` or `buildPythonApplication`
is deprecated with `oldestSupportedRelease = 2511`.
Passing `python.stdenv` to `buildPythonApplication` doensn't do anything

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

@@ -5,6 +5,7 @@
   replaceVars,
   isPyPy,
   python,
+  stdenv,
   setuptools,
   pillow,
   pycairo,
@@ -27,7 +28,7 @@
   pybind11,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage {
   pname = "python-mapnik";
   version = "4.1.3.unstable-2025-09-25";
   pyproject = true;
@@ -49,8 +50,6 @@ buildPythonPackage rec {
     })
   ];
 
-  stdenv = python.stdenv;
-
   build-system = [ setuptools ];
 
   nativeBuildInputs = [