Release note for cps-change-event toggle

- Release notes to enable and disable the toggle functionality
  introduced.
- If the CPS change events are of no interest to them then they can be
  disabled by the environment variable CPS_CHANGE_EVENT_NOTIFICATIONS_ENABLED

Issue-ID: CPS-2211
Change-Id: If2fddb6a499e24194b3eeca2ecdf99b8fb5ec687
Signed-off-by: mpriyank <priyank.maheshwari@est.tech>
diff --git a/docs/release-notes.rst b/docs/release-notes.rst
index bd85137..a7093c7 100644
--- a/docs/release-notes.rst
+++ b/docs/release-notes.rst
@@ -39,6 +39,7 @@
 Bug Fixes
 ---------
 3.4.9
+    - `CPS-2211 <https://jira.onap.org/browse/CPS-2211>`_ Toggle switch to disable CPS Core change events if not used by application. Set CPS_CHANGE_EVENT_NOTIFICATIONS_ENABLED environment variable for the same.
 
 Features
 --------