How Extensions are affected by the Legacy Twitch API v5 shutdown

[BarryCarlyon]

@jbulava

To provide a migration path, these endpoints have been moved to the Twitch API. While there are some updates to the request parameters and return payloads, they function essentially the same as before. A new Extensions section of the Twitch API reference has been added for Extensions starting with Get Extension Configuration Segment.

PLEASE! Add//move them to the extensiosn reference instead

I feel it beneficial to keep the extensions group of endpoints in the extensions reference

Extension API endpoints in Twitch API reference?

Also the extensions reference needs a deprecation banner for the old endpoints.