公众号语音，接收到的Recognition为空？
<xml><ToUserName><![CDATA[gh_b4267ccd61db]]></ToUserName>
<FromUserName><![CDATA[otW9G6Dh0RZEhFbuWbgbemuw8iBM]]></FromUserName>
<CreateTime>1689129897</CreateTime>
<MsgType><![CDATA[voice]]></MsgType>
<MediaId><![CDATA[KPUTDYJMgkjfEhwqQJOqUEExn4Ibrp5TqXO5GZfo2KRjRHEl2E4su0ti7qqoVJkg]]></MediaId>
<Format><![CDATA[amr]]></Format>
<MsgId>7254757666310848512</MsgId>
<Recognition><![CDATA[]]></Recognition>
</xml>
