Test: disable asyncio reactor on Windows for Py>=3.8

tests/test_crawler.py

@@ -373,6 +373,9 @@ class CrawlerProcessSubprocess(ScriptRunnerMixin, unittest.TestCase):
         self.assertIn("Using asyncio event loop: uvloop.Loop", log)
         self.assertIn("async pipeline opened!", log)
 
+    # https://twistedmatrix.com/trac/ticket/9766
+    @skipIf(platform.system() == 'Windows' and sys.version_info >= (3, 8),
+            "the asyncio reactor is broken on Windows when running Python ≥ 3.8")
     def test_default_loop_asyncio_deferred_signal(self):
         log = self.run_script("asyncio_deferred_signal.py")
         self.assertIn("Spider closed (finished)", log)