Disable unused event warning

src/Markup/Avalonia.Markup/AlwaysEnabledDelegateCommand.cs

@@ -14,7 +14,9 @@ namespace Avalonia.Markup
             this.action = action;
         }
 
+#pragma warning disable 0067
         public event EventHandler CanExecuteChanged;
+#pragma warning restore 0067
 
         public bool CanExecute(object parameter) => true;