Property 'groupChannel' does not exist on type 'SendbirdChat'.ts

// Detailed description of issue.

// If problem, please fill out the below. If question, please delete.
[SDK Version]
// What version of the SDK are you using?
@sendbird/chat”: “^4.9.3”,
[Reproduction Steps]
// Please provide reproduction steps and, if possible, code snippets.
Follow steps in getting started and attempt to add an addGroupChannelHandler.
// How frequently is this issue occurring?
[Current impact]
// How is this currently impacting your implementation?
I don’t know how to migrate from v3 → v4 with this issue.