Destination for one platform/channel/livestream chat.
adapter is any module implementing GelotvBot.Adapter. rate_limit accepts
:limit, :interval, and optional :burst values:
%GelotvBot.Target{
platform: :twitch,
channel: "gelotv",
adapter: MyApp.TwitchAdapter,
rate_limit: [limit: 20, interval: 30_000, burst: 5]
}