python.pkgs.pytest-django: fix patch hash

pkgs/development/python-modules/pytest-django/default.nix

···
-{ stdenv, buildPythonPackage, fetchurl
+{ stdenv, buildPythonPackage, fetchPypi
 , pytest, django, setuptools_scm
 , fetchpatch
 }:
···
   name = "${pname}-${version}";
   version = "3.1.2";
 
-  src = fetchurl {
-    url = "mirror://pypi/p/pytest-django/${name}.tar.gz";
+  src = fetchPypi {
+    inherit pname version;
     sha256 = "02932m2sr8x22m4az8syr8g835g4ak77varrnw71n6xakmdcr303";
   };
 
···
     # Unpin setuptools-scm
     (fetchpatch {
       url = "https://github.com/pytest-dev/pytest-django/commit/25cbc3b395dcdeb92bdc9414e296680c2b9d602e.patch";
-      sha256 = "1mx06y4kz2zs41mb2h9bh5p4jc6s6hfsq6fghhsks5b7qak05xjp";
+      sha256 = "0mz3rcsv44pfzlxy3pv8mx87glmv34gy0d5aknvbzgb2a9niryws";
     })
   ];