Slightly improve wording

'Layer data' is a bit technical.

plugins/SimulationView/SimulationView.py

@@ -118,7 +118,7 @@ class SimulationView(CuraView):
 
         self._wireprint_warning_message = Message(catalog.i18nc("@info:status", "Cura does not accurately display layers when Wire Printing is enabled."),
                                                   title = catalog.i18nc("@info:title", "Simulation View"))
-        self._slice_first_warning_message = Message(catalog.i18nc("@info:status", "Nothing is shown because you need to slice first."), title = catalog.i18nc("@info:title", "No layer data"))
+        self._slice_first_warning_message = Message(catalog.i18nc("@info:status", "Nothing is shown because you need to slice first."), title = catalog.i18nc("@info:title", "No layers to show"))
 
         QtApplication.getInstance().engineCreatedSignal.connect(self._onEngineCreated)