webrtcbin: Incorrect demonstration of usage of promise in webrtcbidirectional.c
In the test example "webrtcbidirectional.c", inside the _on_answer_received
API, it is mentioned that there are two ways to tell webrtcbin that we don't want to be notified when the task is complete.
The second way shows the usage by interrupting a promise. Although the promise is created and interrupted in the code, it is never passed as a parameter in the emitted signal.