Deprecate org.springframework.data.elasticsearch.client.ClientLogger

[sothawo]

org.springframework.data.elasticsearch.client.ClientLogger can be used to log request and responses on trace level. This is not needed anymore, as Elasticsearch's RestClient can do this (see https://www.elastic.co/guide/en/elasticsearch/client/java-api-client/current/java-rest-low-usage-logging.html) by settting the log level of the tracer package to "trace".

So we deprecate this class to remove it later.