Set the pointer before connecting to it.

This fixes the warning "QObject::connect: invalid null parameter"

src/scriptengines/qml/plasmoid/appletinterface.cpp

@@ -386,10 +386,10 @@ void AppletInterface::setToolTipItem(QQuickItem *toolTipItem)
         return;
     }
 
+    m_toolTipItem = toolTipItem;
     connect(m_toolTipItem.data(), &QObject::destroyed,
             this, &AppletInterface::toolTipItemChanged);
 
-    m_toolTipItem = toolTipItem;
     emit toolTipItemChanged();
 }