token property
log in by using appID + token.
The token issued by the developer's business server is used to ensure security. Please note that if you want to use appID + token login, do not assign a value to appSign
For the generation rules, please refer to Using Token Authentication
(https://doc-zh.zego.im/article/10360), the default is an empty string, that is, no authentication.
if appSign is not passed in or if appSign is empty, this parameter must be set for authentication when logging in to a room.
Implementation
final String token;