[Docs] Incorrectly listed requirement for Send Extension Chat Message Endpoint

[Marenthyu]

Brief description
In the Docs, it is written A signed JWT must include the role and channel_id fields for the Send Extension Chat Message Endpoint. This is not true, as the channel_id field seems to be completely ignored when calling this Endpoint. Instead, the value of user_id seems to be required and used, as the Schema dictates. (Note that it does not need to match the broadcaster_id, as it just denotes the Extension owner, not the target broadcaster)

Expected documentation
It should list user_id as the required matching field and not mention channel_id, as it is ignored.

Screenshots
https://lowee.de/chrome_2022-02-19_20-22-44.png

Additional context or questions
See also Discord Discussion: https://discord.com/channels/504015559252377601/523676096277905419/944671207909908610
@BarryCarlyon used his testing code to verify the above information.

[BarryCarlyon]

Authorization
Signed JWT created by an Extension Backend Service (EBS), following the requirements documented in [Signing the JWT](https://dev.twitch.tv/docs/extensions/building/#signing-the-jwt). A signed JWT must include the role and channel_id fields documented in [JWT Schema](https://dev.twitch.tv/docs/extensions/reference/#jwt-schema). role must be set to "external" and channel_id must match the broadcaster ID in the request URL.

Should read just

Authorization
Signed JWT created by an Extension Backend Service (EBS), following the requirements documented in [Signing the JWT](https://dev.twitch.tv/docs/extensions/building/#signing-the-jwt).

As the first linked to section is correct. And the second sentence is just superflous

And the sentence

A signed JWT must include the role field documented in [JWT Schema](https://dev.twitch.tv/docs/extensions/reference/#jwt-schema), and role must be set to "external".

On any of the JWT basend endpoints is generaly superflous.
Since if you can do external or "the JWT passed from the frontend to an EBS that belongs to the broadcaster"

This applies to PubSub (channel/channel whisper), Config Service (broadcaster segement), Extension Chat when the ChannelID used for these endpoints is the same as the channelID being talked to (in query params) and the JWT was generated by Twitch (not external)

[scott-a-white]

Thanks for reporting the issue. Fixed: https://dev.twitch.tv/docs/api/reference#send-extension-chat-message.