Codechange: use default dtor instead of empty (#10826)

src/settings_gui.cpp

@@ -957,7 +957,7 @@ struct BaseSettingEntry {
 	byte level; ///< Nesting level of this setting entry
 
 	BaseSettingEntry() : flags(0), level(0) {}
-	virtual ~BaseSettingEntry() {}
+	virtual ~BaseSettingEntry() = default;
 
 	virtual void Init(byte level = 0);
 	virtual void FoldAll() {}