Add changelog entry

Signed-off-by: Suraj Singh <[email protected]>

CHANGELOG.md

@@ -12,6 +12,8 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Support for HTTP/2 (server-side) ([#3847](https://github.com/opensearch-project/OpenSearch/pull/3847))
 - BWC version 2.2.2 ([#4383](https://github.com/opensearch-project/OpenSearch/pull/4383))
 - Support for labels on version bump PRs, skip label support for changelog verifier ([#4391](https://github.com/opensearch-project/OpenSearch/pull/4391))
+- Update previous release bwc version to 2.4.0 ([#4455](https://github.com/opensearch-project/OpenSearch/pull/4455))
+
 ### Dependencies
 - Bumps `org.gradle.test-retry` from 1.4.0 to 1.4.1
 - Bumps `reactor-netty-core` from 1.0.19 to 1.0.22
@@ -78,4 +80,4 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 
 [Unreleased]: https://github.com/opensearch-project/OpenSearch/compare/2.2.0...HEAD
-[2.x]: https://github.com/opensearch-project/OpenSearch/compare/2.2.0...2.x
+[2.x]: https://github.com/opensearch-project/OpenSearch/compare/2.2.0...2.x