Update CHANGELOG

Author: wamaral

CHANGELOG.md

@@ -4,6 +4,7 @@ Changes and additions to the library will be listed here.
 
 ## Unreleased
 
+- Refresh a stale cluster's metadata if necessary on `Kafka::Client#deliver_message` (#901).
 - Fix `Kafka::TransactionManager#send_offsets_to_txn` (#866).
 - Add support for `murmur2` based partitioning.
 - Add `resolve_seed_brokers` option to support seed brokers' hostname with multiple addresses (#877).