[MD] Adding unit test coverage for Update data source management (#2567) (#2589)

Signed-off-by: mpabba3003 <amazonmanideep@gmail.com>
(cherry picked from commit 115105a)

Co-authored-by: Manideep Pabba <109986843+mpabba3003@users.noreply.github.com>

Author: opensearch-trigger-bot[bot]

CHANGELOG.md

@@ -42,6 +42,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ### 🪛 Refactoring
 
 ### 🔩 Tests
+* [Multi DataSource] Add unit test coverage for Update Data source management stack  ([#2567](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/2567))
 
 ## [2.x]
 ### 💥 Breaking Changes