Notification Email Hourly/Daily/Weekly Sender are received by simple user with Live email notifications

Preconditions: 

• The Mail Sending should be configured: Configure Mail Sending
• An user exists and has an email address set in its profile
• From webapps\xwiki\WEB-INF\xwiki.properties set notifications.emails.live.graceTime = 1 to enable the sending of e-mails after 1 minute. Make sure the line is not commented out (doesn't have an # at the start of it).

Steps to reproduce:

1. Log in as a simple user (with email address in the profile)
2. Click on the bell in the top right corner
3. Click on Settings, in the right side of Notifications
4. Set "Email Frequency" to Live
5. Set ON all the options in the Email column
6. Log in with another user or with Admin
7. Create/update/delete a page
8. Comment in another page

Expected results: The user receives emails with the changes made.

Actual results: The user receives first 3 emails with Notification Email Hourly Sender, Notification Email Daily Sender and Notification Email Weekly Sender then the expected emails.

Note: Tested on 10.8 standard and the emails are sent correctly. No Notifications emails senders are received.