Add changelog

Signed-off-by: Hyunsang Han <[email protected]>

Author: HyunSangHan

CHANGELOG.md

@@ -76,6 +76,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Add skiplist optimization to auto_date_histogram aggregation ([#20057](https://github.com/opensearch-project/OpenSearch/pull/20057))
 - Throw exceptions for currently unsupported GRPC request-side fields ([#20162](https://github.com/opensearch-project/OpenSearch/pull/20162))
 - Handle custom metadata files in subdirectory-store ([#20157](https://github.com/opensearch-project/OpenSearch/pull/20157))
+- Skip metadata upload when no new segments need uploading during refresh for remote store clusters ([#19198](https://github.com/opensearch-project/OpenSearch/pull/19198))
 
 ### Fixed
 - Fix Allocation and Rebalance Constraints of WeightFunction are incorrectly reset ([#19012](https://github.com/opensearch-project/OpenSearch/pull/19012))