Remove virtual keyword. (#4992)

SetupUI()is called in the AssetEditorMainWindow constructor - it should not be virtual. Derived classes will not receive the call.

Signed-off-by: Andre Mitchell <andre.mitchell@bytesofpi.com>

Gems/GraphCanvas/Code/StaticLib/GraphCanvas/Widgets/GraphCanvasEditor/GraphCanvasAssetEditorMainWindow.h

@@ -89,7 +89,7 @@ namespace GraphCanvas
         explicit AssetEditorMainWindow(AssetEditorWindowConfig* config, QWidget* parent = nullptr);
         virtual ~AssetEditorMainWindow();
         
-        virtual void SetupUI();
+        void SetupUI();
         void SetDropAreaText(AZStd::string_view text);        
 
         const EditorId& GetEditorId() const;