test(music): ensure fork concurrency is set by default

Set the default concurrency to 'fork' in the MusicTest to ensure that the tests
run in a forked environment. This change also skips the 'songs' test group on
Windows to align with platform-specific execution considerations.

Author: guanguans

composer.lock

@@ -25,9 +25,9 @@
     //
     //     return $mockMusic->makePartial();
     // });
+    config()->set('concurrency.default', 'fork');
     expect(app(Music::class))->search('腰乐队', config('app.sources'))->toBeInstanceOf(Collection::class);
-})->group(__DIR__, __FILE__)->with('songs');
-
+})->group(__DIR__, __FILE__)->with('songs')->skipOnWindows();
 it('will throw exception when download failed', function (): void {
     try {
         app(Music::class)->download('foo.mp3', downloads_path('foo.mp3'));