### _Why are the changes needed?_

Update `.asf.yaml` to redirect Issues/PR Notifications to notificationskyuubi.apache.org

### _How was this patch tested?_

No test needed

Closes #2042 from zjffdu/notification.

Closes #2042

1f16cb4a [Jeff Zhang] Redirect Issues/PR Notifications to notifications@kyuubi.apache.org
Authored-by: Jeff Zhang <zjffdu@apache.org>
Signed-off-by: Kent Yao <yao@apache.org>