Update release notes for version 11.2.0

Added details about transferTag feature in billing section.

Author: kofemann

release-notes-11.2

@@ -78,6 +78,10 @@ HTML header: <title>dCache 11.2 Release Notes</title>
 
 ### Admin
 
+### Billing
+
+The transferTag is used by clients to label transfers with activity-specific information, such as experiment ID and workflow ID. This information is currently provided by XRootD and HTTP clients, and can be used by monitoring systems to identify data flows. Starting version 11.2.0 dCache includes transferTag information into the generated JSON records.
+
 ### Chimera
 
 ### Cleaner