783 cleanup webrtc on cti ws close
Closes #783
Based on !32 (merged), to be merged after both !31 (closed) and !32 (merged).
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Closes #783
Based on !32 (merged), to be merged after both !31 (closed) and !32 (merged).