update pr link in the changelog.md

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

CHANGELOG.md

@@ -137,7 +137,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Remove `ui-select` dev dependency ([#5660](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5660))
 - Bump `chromedriver` dependency to `121.0.1"` ([#5926](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5926))
 - Add @ruanyl as a maintainer ([#5982](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5982))
-- Add @BionIT as a maintainer ([#5985](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5985))
+- Add @BionIT as a maintainer ([#5988](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5988))
 
 ### 🪛 Refactoring