add changelog

Signed-off-by: abbyhu2000 <[email protected]>

Author: abbyhu2000

CHANGELOG.md

@@ -24,6 +24,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - [Discover] Display inner properties in the left navigation bar [#5429](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5429)
 - [Chrome] Introduce registerCollapsibleNavHeader to allow plugins to customize the rendering of nav menu header ([#5244](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5244))
 - [Custom Branding] Relative URL should be allowed for logos ([#5572](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5572))
+- [Data Explorer] Adding PPL to query language selector ([#5623](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5623))
 
 ### 🐛 Bug Fixes