modify changelog to reflect the latest change

Author: ruai0511

CHANGELOG.md

@@ -113,6 +113,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Add kuromoji_completion analyzer and filter ([#4835](https://github.com/opensearch-project/OpenSearch/issues/4835))
 - The org.opensearch.bootstrap.Security should support codebase for JAR files with classifiers ([#12586](https://github.com/opensearch-project/OpenSearch/issues/12586))
 - Make search query counters dynamic to support all query types ([#12601](https://github.com/opensearch-project/OpenSearch/pull/12601))
+- Add a counter to node stat api to track shard going from idle to non-idle ([#12737](https://github.com/opensearch-project/OpenSearch/pull/12737))
 
 ### Dependencies
 - Bump `peter-evans/find-comment` from 2 to 3 ([#12288](https://github.com/opensearch-project/OpenSearch/pull/12288))