Updated Changelog to reflect Rack info as well

CHANGELOG.md

@@ -7,7 +7,8 @@ v2.3.0 is a feature release with the following features, fixes and enhancements:
  * Add support for AdminAPI `DescribeCluster()` and `DescribeTopics()`. (@jainruchir, #1635)
  * [KIP-430](https://cwiki.apache.org/confluence/display/KAFKA/KIP-430+-+Return+Authorized+Operations+in+Describe+Responses):
    Return authorized operations in Describe Responses. (@jainruchir, #1635)
-
+ * Add `Rack` to the `Node` type, so AdminAPI calls can expose racks for brokers
+   (currently, all Describe Responses) (#1635, @jainruchir).
 
 confluent-kafka-python is based on librdkafka v2.3.0, see the
 [librdkafka release notes](https://github.com/confluentinc/librdkafka/releases/tag/v2.3.0)