Update link content

Update link content to set user expectations about where the link will take them.

app/templates/views/api/callbacks/delivery-status-callback.html

@@ -19,7 +19,7 @@
 
       <p>
         When you send an email or text message, we can tell you if Notify was able to deliver it.
-        Check the <a href="{{ url_for('.callbacks') }}"> callback documentation </a> for more information.
+        Read the Callbacks section of the <a href="{{ url_for('main.documentation') }}">documentation</a> for more information.
       </p>
 
       {% call form_wrapper() %}