fix: fix the json serialization for the payload channel rtp event

[mhammo]

The rust package throws the following errors when trying to ingest DirectTransport's rtp event from the C++ process.

[2022-10-18T13:52:32Z ERROR mediasoup::worker] worker[id:6f303805-5d89-48e2-813c-7a2e1709770e] unexpected payload channel data: {"targetId":"49a8b34a-b64f-49d7-81f5-09fd10c20d00","event":"rtp}
[2022-10-18T13:52:32Z ERROR mediasoup::worker] worker[id:6f303805-5d89-48e2-813c-7a2e1709770e] unexpected payload channel data: {"targetId":"49a8b34a-b64f-49d7-81f5-09fd10c20d00","event":"rtp}
[2022-10-18T13:52:32Z ERROR mediasoup::worker] worker[id:6f303805-5d89-48e2-813c-7a2e1709770e] unexpected payload channel data: {"targetId":"fc977b9b-0632-493d-b964-a93691d52083","event":"rtp}
[2022-10-18T13:52:32Z ERROR mediasoup::worker] worker[id:6f303805-5d89-48e2-813c-7a2e1709770e] unexpected payload channel data: {"targetId":"49a8b34a-b64f-49d7-81f5-09fd10c20d00","event":"rtp}
[2022-10-18T13:52:32Z ERROR mediasoup::worker] worker[id:6f303805-5d89-48e2-813c-7a2e1709770e] unexpected payload channel data: {"targetId":"49a8b34a-b64f-49d7-81f5-09fd10c20d00","event":"rtp}

The error shows what the issue is, a serialization issue for payload channel events that do not use the json data parameter.
I've applied the below fix locally and the error has disappeared, and I'm able to ingest and use the media data.

[nazar-pc]

Strong types are awesome, aren't they?)
Yeah, this was obviously a typo, thanks for reporting and fixing!

It will affect both Rust and TypeScript BTW. I'll probably do a new Rust release with latest improvements tomorrow.

[ibc]

Thanks for this.

BTW we should have a mechanism to not forget to update CHANGELOG.md file (I'm open to suggestions).