OpenChannelParams constructor Null safety

1. sendbird_sdk
2. open_channel_params
3. OpenChannelParams
4. OpenChannelParams constructor

OpenChannelParams class

1. Constructors
2. OpenChannelParams
3. Properties
4. channelUrl
5. coverImage
6. customType
7. data
8. hashCode
9. name
10. operatorUserIds
11. runtimeType
12. Methods
13. noSuchMethod
14. toJson
15. toString
16. Operators
17. operator ==