MessageContentEvent(Message content event)

{
    "is_canceled": false,
    "name": "Some name",
    "description": "Some description",
    "join_link": "https://call.whatsapp.com/voice/K5IFl19olpzTLsh52A0G9R",
    "start": 1675964377,
    "responses": [
        {
            "participant": "string",
            "response": "UNKNOWN",
            "timestamp": 1675964377
        }
    ]
}