Update notification-types.rst

Added a WhatsApp section

Author: cmillane-splunk

sp-oncall/notifications/notification-types.rst

@@ -72,6 +72,13 @@ incident number, entity_display_name, and response code if two-way SMS is suppor
 
 You may stop and start our SMS notification subscription by replying to the message with STOP or START. Although, it is best to manage your notifications from the personal profile page in Splunk On-Call.
 
+.. raw:: html
+
+  <embed>
+    <h2>WhatsApp</h2>
+  </embed>
+
+WhatsApp notifications can be used in your personal paging policy.  To enable WhatsApp, please download and configure the WhatsApp application from the Apple App Store or Google Play Store.  Next, access your user profile in Splunk On-Call and enter and verify your mobile number.  Once verified, an :guilabel:`Enable WhatsApp` button will appear next to the number.  After following the verification prompts, you will be able to use WhatsApp in your Paging Policy.
 
 .. raw:: html