Configure chat view model.

ChatListTableView.swift

private func configureViewModel() {
        
        guard let name = nickName else {
            return
        }
        
        chatViewModel.arrUsers.subscribe {[weak self] (result: [User]) in
            
            guard let self = self else {
                return
            }
            
            self.reloadData()
        }
        
        chatViewModel.fetchParticipantList(name)
    }