Hi. I'm not sure when is going to be available for DataFlow. You can try connecting from PowerBi Desktop and then copy the PowerQueryM code to the Dataflow. That has worked for me with other connectors that weren't there.
I hope that helps,
P/D The doc might show cosmos because it is available at PowerBi Desktop
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.
Happy to help!