DOCSP-47839 added banner to RN

Author: kanchana-mongodb

source/release-notes.txt

@@ -20,6 +20,15 @@ Release Notes for |bi|
 .. expect and we don't break the links on the downloads page.
 .. (DOCS-9670 for context)
 
+.. note:: Release notes mention only releases with feature changes
+
+   MongoDB releases the |bi| in a continuous deployment manner. This
+   release cadence allows us to continuously maintain the |bi|
+   performance and stability. These release notes capture only those
+   releases that contain direct user feature changes. If a particular
+   |bi| release contains only performance and stability improvements, it
+   may not be included in these release notes. 
+
 .. _bi-2-14-22:
 
 |bi| 2.14.22