Profiler: Don't return constant copies of GUI::ModelIndex

Userland/DevTools/Profiler/FlameGraphView.cpp

@@ -50,7 +50,7 @@ FlameGraphView::FlameGraphView(GUI::Model& model, int text_column, int width_col
     layout_bars();
 }
 
-GUI::ModelIndex const FlameGraphView::hovered_index() const
+GUI::ModelIndex FlameGraphView::hovered_index() const
 {
     if (!m_hovered_bar)
         return GUI::ModelIndex();

Userland/DevTools/Profiler/FlameGraphView.h

@@ -25,7 +25,7 @@ public:
 
     Function<void()> on_hover_change;
 
-    GUI::ModelIndex const hovered_index() const;
+    GUI::ModelIndex hovered_index() const;
 
 protected:
     virtual void model_did_update(unsigned flags) override;