[Data Explorer] Removed X icon in data source selection. (#5238)

* removed X icon in data source selection.

Signed-off-by: Abhilash <abhilash.bhimanna@senecaglobal.com>

* updated changelog

Signed-off-by: Abhilash <abhilash.bhimanna@senecaglobal.com>

* Update CHANGELOG.md

Signed-off-by: Miki <amoo_miki@yahoo.com>

---------

Signed-off-by: Abhilash <abhilash.bhimanna@senecaglobal.com>
Signed-off-by: Ashwin P Chandran <ashwinpc@amazon.com>
Signed-off-by: Miki <amoo_miki@yahoo.com>
Co-authored-by: Abhilash <abhilash.bhimanna@senecaglobal.com>
Co-authored-by: Ashwin P Chandran <ashwinpc@amazon.com>
Co-authored-by: Miki <amoo_miki@yahoo.com>

CHANGELOG.md

@@ -65,6 +65,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - [Data Explorer][Discover] Allow data grid to auto adjust size based on fetched data count ([#5191](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5191))
 - [BUG] Fix wrong test due to time conversion ([#5174](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5174))
 - [BUG][Data Explorer][Discover] Allow filter and query persist when refresh page or paste url to a new tab ([#5206](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5206))
+- [Data Explorer] Remove the `X` icon in data source selection field ([#5238](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5238))
 - [BUG][Fuctional Test] Make setDefaultAbsoluteRange more robust and update doc views tests ([#5242](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5242))
 
 ### 🚞 Infrastructure

src/plugins/data/public/data_sources/datasource_selector/datasource_selectable.tsx

@@ -128,6 +128,7 @@ export const DataSourceSelectable = ({
       selectedOptions={selectedSources as any}
       onChange={handleSourceChange}
       singleSelection={singleSelection}
+      isClearable={false}
       async
     />
   );