update Dart cli_windows example

examples/dart/cli_windows/lib/thermion_window.g.dart

@@ -2,7 +2,7 @@
 //
 // Generated by `package:ffigen`.
 // ignore_for_file: type=lint
-@ffi.DefaultAsset('package:cli_windows/thermion_window.dart')
+@ffi.DefaultAsset('package:cli_windows/cli_windows.dart')
 library;
 
 import 'dart:ffi' as ffi;