How can I embed html into my Flutterflow project?

I am wanting to integrate a Hubspot chatbot into my web app built on FlutterFlow however have not yet managed to do so. I need to paste the below code into the body tag of my index.html file:

<!-- Start of HubSpot Embed Code -->
  <script type="text/javascript" id="hs-script-loader" async defer src="//js-eu1.hs-scripts.com/my_tracking_code.js"></script>
<!-- End of HubSpot Embed Code -->

Any help would be appreciated.

I have used the new FlutterFlow extension on vs code however we are not yet able to edit this file using this feature.