update changelog to include db config connection return value change (#14256)

changelog/14033.txt

@@ -1,3 +1,7 @@
 ```release-note:feature
 **Database plugin multiplexing**: manage multiple database connections with a single plugin process
 ```
+
+```release-note:change
+plugin/database: The return value from `POST /database/config/:name` has been updated to "204 No Content"
+```