add CHANGELOG entry

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

Author: kaushalmahi12

CHANGELOG.md

@@ -88,6 +88,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Fix _list/shards API failing when closed indices are present ([#16606](https://github.com/opensearch-project/OpenSearch/pull/16606))
 - Fix remote shards balance ([#15335](https://github.com/opensearch-project/OpenSearch/pull/15335))
 - Always use `constant_score` query for `match_only_text` field ([#16964](https://github.com/opensearch-project/OpenSearch/pull/16964))
+- [WLM] Add WLM support for search scroll API ([#16981](https://github.com/opensearch-project/OpenSearch/pull/16981))
 
 ### Security