Remove changelog

Signed-off-by: Binlong Gao <gbinlong@amazon.com>

Author: gaobinlong

CHANGELOG.md

@@ -24,7 +24,6 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Change implementation for `percentiles` aggregation for latency improvement ([#19648](https://github.com/opensearch-project/OpenSearch/pull/19648))
 - Refactor the ThreadPoolStats.Stats class to use the Builder pattern instead of constructors ([#19306](https://github.com/opensearch-project/OpenSearch/pull/19306))
 - Refactor the IndexingStats.Stats class to use the Builder pattern instead of constructors ([#19306](https://github.com/opensearch-project/OpenSearch/pull/19306))
-- Replace explicit type conversion with instanceof pattern variable in org.opensearch.search package ([#19714](https://github.com/opensearch-project/OpenSearch/pull/19714))
 
 ### Fixed
 - Fix Allocation and Rebalance Constraints of WeightFunction are incorrectly reset ([#19012](https://github.com/opensearch-project/OpenSearch/pull/19012))