Notifications - Make "Mark All as Read" disabled if all notifications already read

**Describe the bug**
When all notifications already read, the "Mark All as Read" link still active

**To Reproduce**
Steps to reproduce the behavior:
1. Go to the Notification Panel
2. Click on Mark All as Read
3. Note the link still active

**Expected behavior**
"Mark All as Read" need be disabled state if all notifications already read
