Change loglevel of cancelled errors to info

[Laityned]

copy of PR 2404 on base repo

See dpkp#1583

When closing the connection on purpose by calling consumer.close(), each ongoing Fetch request will be cancelled, by setting a Cancelled KafkaException on that particular request.

Due to the error callback on this object, which is nothing else except a logging statement, the cancellation will be logged with level ERROR, instead as INFO, while it is not actually an error, but a way of stopping the ongoing request