Add upgrade note

Author: patel-vansh

user_guide_src/source/installation/upgrade_480.rst

@@ -73,6 +73,8 @@ and it is recommended that you merge the updated versions with your application:
 Config
 ------
 
+- app/Config/Filters.php
+    - Added a new filter named ``requestid`` that adds a unique request ID to each request in the application's context.
 - app/Config/Mimes.php
     - ``Config\Mimes::$mimes`` added a new key ``md`` for Markdown files.
 - app/Config/Security.php