Core: Drop Q_OBJECT in PresentationModeHandler

Not needed.

Change-Id: Ia6416071f303fd456dc4094aabfeb63acbb226c2
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/coreplugin/actionmanager/actionmanager.cpp

@@ -34,8 +34,6 @@ namespace Core::Internal {
 
 class PresentationModeHandler : public QObject
 {
-    Q_OBJECT
-
 public:
     void connectCommand(Command *command);
 
@@ -520,5 +518,3 @@ void ActionManagerPrivate::saveSettings()
         saveSettings(j.value());
     }
 }
-
-#include "actionmanager.moc"