[PD] remove Python.h from headers

seems not to be necessary anymore

src/Mod/PartDesign/App/AppPartDesignPy.cpp

@@ -20,18 +20,14 @@
  *                                                                         *
  ***************************************************************************/
 
-
 #include "PreCompiled.h"
 
-#ifndef _PreComp_
-# include <Python.h>
-#endif
-
 #include <Base/GeometryPyCXX.h>
 #include <Base/Interpreter.h>
 #include <Base/VectorPy.h>
 #include <Base/Tools.h>
 
+
 namespace PartDesign {
 class Module : public Py::ExtensionModule<Module>
 {