Update test_flusher.py

Author: curusarn

tests/test_flusher.py

@@ -144,7 +144,7 @@ def uploader(frame):
         self.assertFalse(fw.should_run)
 
     # test relies on overriding excepthook which is available from 3.8+
-    @unittest.skipIf(sys.version_info <= (3, 7))
+    @unittest.skipIf(sys.version_info <= (3, 7), "Test skipped because overriding excepthook is not available on Python 3.7 and lower")
     def test_shutdown_dont_raise_exception_in_thread(self):
         original_excepthook = threading.excepthook
         threading.excepthook = mock.Mock()