add PR link in CHANGELOG

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

Author: kaushalmahi12

CHANGELOG.md

@@ -91,7 +91,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Fix array hashCode calculation in ResyncReplicationRequest ([#16378](https://github.com/opensearch-project/OpenSearch/pull/16378))
 - Fix missing fields in task index mapping to ensure proper task result storage ([#16201](https://github.com/opensearch-project/OpenSearch/pull/16201))
 - Fix typo super->sb in method toString() of RemoteStoreNodeAttribute ([#15362](https://github.com/opensearch-project/OpenSearch/pull/15362))
-- [Workload Management] query group create/update APIs were not properly setup
+- [Workload Management] query group create/update APIs were not properly setup ([16422](https://github.com/opensearch-project/OpenSearch/pull/16422))
 
 ### Security