add CHANGELOG entry

Signed-off-by: Kaushal Kumar <[email protected]>

CHANGELOG.md

@@ -85,6 +85,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - [Streaming Indexing] Fix intermittent 'The bulk request must be terminated by a newline [\n]' failures [#16337](https://github.com/opensearch-project/OpenSearch/pull/16337))
 - Fix wrong default value when setting `index.number_of_routing_shards` to null on index creation ([#16331](https://github.com/opensearch-project/OpenSearch/pull/16331))
 - Fix disk usage exceeds threshold cluster can't spin up issue ([#15258](https://github.com/opensearch-project/OpenSearch/pull/15258)))
+- [Workload Management] Fix query group persisting bug [#16370](https://github.com/opensearch-project/OpenSearch/pull/16370)
 
 - Fix inefficient Stream API call chains ending with count() ([#15386](https://github.com/opensearch-project/OpenSearch/pull/15386))