Workflow Microsoft Teams PowerApps – How to Remove Footer from Microsoft Teams Message Sent with PowerApps Workflow

Microsoft is retiring the Office 365 connectors from Microsoft Teams, including the webhook one that allows automatic messaging through very simple POST message (see this devblog from microsoft).

I am switching to the given solution of using a PowerApps flow named : Post to a channel when a webhook request is received

Everything is working great but I have a deeply, ugly, and irritating footer that is added to every message (and sometimes, when using action buttons, not at the bottom). It is written "[USERNAME] used a Workflow template to send this card. Get template".

How can I disable the footer in my JSON request. My current body is :

{
        "type": "message",
        "attachments": [ {
            "contentType":"application/vnd.microsoft.card.adaptive",
             "contentUrl":null,
             "content":{
                "$schema":"http://adaptivecards.io/schemas/adaptive-card.json",
                "type":"AdaptiveCard",
                "version":"1.2",
                "msteams": {
                    "width": "Full",
                },
                "body":[
                    {
                        "type": "TextBlock",
                        "size": "medium",
                        "weight": "bolder",
                        "text": "Header Text",
                        "style": "heading",
                        "wrap": false
                    },
                    {
                        "type": "TextBlock",
                        "text": "Simple text"
                        "wrap": true
                    }
                ]
            }
        }
    ]
}