[BUG] When sending an mp3 file, it has no filename

[Lunsit]

Describe the bug
A clear and concise description of what the bug is.When sending an mp3 file, it has no filename

To Reproduce
Steps to reproduce the behavior:

1. Send an mp3 file.
2. The file name in WeChat is displayed as 'None - None.mp3'

Expected behavior
A normal file name.

Screenshots

Version information (please complete the following information):

• OS: Ubuntu 20.04.3 LTS

Version: 2.1.1
Python version:
3.8.10 (default, Nov 26 2021, 20:14:08) 
[GCC 9.3.0]
Running on profile "default".

Master channel:
    Telegram Master (blueset.telegram) 2.2.5.dev2 # Default instance

Slave channel:
    WeChat Slave (blueset.wechat) 2.0.7 # Default instance

Middlewares:
    No middleware is enabled.