Cheats Manager: Fix factory widget spacing

Add stretch to bottom of factory widget to prevent the Data Type
QGroupBox from getting stretched out awkwardly.

Source/Core/DolphinQt/CheatSearchFactoryWidget.cpp

@@ -123,6 +123,8 @@ void CheatSearchFactoryWidget::CreateWidgets()
   m_new_search = new NonDefaultQPushButton(tr("New Search"));
   layout->addWidget(m_new_search);
 
+  layout->addStretch();
+
   setLayout(layout);
 }