In async transport initialization readyWatcher will never be called in case of discovery error #294

https://github.com/ydb-platform/ydb-java-sdk/blob/master/core/src/main/java/tech/ydb/core/impl/YdbTransportImpl.java#L87
If discovery fails, discovery.waitReady will throw exception and readyWatcher.run() will never be called.