pin

pinned Parameter, can Control Whether Update Operation timestamp stamp

Operation result callback

Message unique ID List, at most 20

```kotlin
channel.pin { result, error ->
    if (error == null) {
        if (error == null) {
    }
}

}
channel.pin(PinParams(updateOperationTime = false)) { result, error ->
    // ...
}

======================================== pushContent = "You received a new message"