[Fix] Join slack channel link.
[Fix] Join slack channel link.

cfraz89/RxSwift,ReactiveX/RxSwift,cfraz89/RxSwift,ReactiveX/RxSwift,kzaher/RxSwift,cfraz89/RxSwift,cfraz89/RxSwift,kzaher/RxSwift,kzaher/RxSwift,kzaher/RxSwift,ReactiveX/RxSwift