Python: Use new plugin items setup pattern for PythonEditor

Change-Id: Ie8516960a106ddeff415b6412d9af66f7d2f0f36
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/python/pythonplugin.cpp

@@ -40,7 +40,6 @@ QObject *pluginInstance()
 class PythonPluginPrivate
 {
 public:
-    PythonEditorFactory editorFactory;
     PythonOutputFormatterFactory outputFormatterFactory;
     PythonRunConfigurationFactory runConfigFactory;
     PySideBuildStepFactory buildStepFactory;
@@ -72,6 +71,8 @@ private:
     {
         d = new PythonPluginPrivate;
 
+        setupPythonEditorFactory(this);
+
         KitManager::setIrrelevantAspects(KitManager::irrelevantAspects()
                                          + QSet<Id>{PythonKitAspect::id()});