fix Message.is_scheduled field always False when parsing

Signed-off-by: wulan17 <[email protected]>

pyrogram/dispatcher.py

@@ -66,7 +66,7 @@ def __init__(self, client: "pyrogram.Client"):
         async def message_parser(update, users, chats):
             return (
                 await pyrogram.types.Message._parse(self.client, update.message, users, chats,
-                                                    isinstance(update, UpdateNewScheduledMessage)),
+                                                    is_scheduled=isinstance(update, UpdateNewScheduledMessage)),
                 MessageHandler
             )