Update CHANGELOG.md with PR number

Author: Elfi0Kuhndorf

CHANGELOG.md

@@ -9,7 +9,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 ## [2.4.0] - 2023-12-13
 
 ### Fixed
-* Changed Canvas Sort order of multiple UI elements to enable visibility of RNSM and reconnection attempts during the loading screen
+* Changed Canvas Sort order of multiple UI elements to enable visibility of RNSM and reconnection attempts during the loading screen (#879)
 
 ### Changed
 * Upgraded editor version to 2022.3.14f1 (#871)