Cancel safety/Idle tokio tasks after WebRTC session close

[alexipeck]

I have been trying to diagnose issues within my own project related to WebRTC and after using tokio-console, I started noticing many idle tokio tasks spawned by this library which don't get closed after the WebRTC session should have closed. I have observed 23-24 tasks which stay idle, but the screenshot below shows 18.

I am under the assumption that part may be attributable to missing cancel safety? Note that this screenshot is after running .close() on the peer connection

I started this issue to form a discussion on what's needed within the project to improve cancel safety