User that was deleted from admin group stay logged in

Steps to reproduce:

Preconditions:

• 'Administrators' user group should exist in system, it is set as 'allow' in Components->group permissions->Admin_panel
• 'New user' should exist.

1. Navigate to the uat.jtalk.org/pouple using Chrome
2. Login to the system using admin/admin credential
3. Navigate to the Users - User Groups
4. Add 'New user' to the 'Administrators' user group and save dialog
5. Navigate to the uat.jtalk.org/pouple using Mozilla
6. Login to the system using 'New user' credential
   Actual/Expected: A user with admin permissions can log in
7. On the Chrome browser remove the user from step 4
8. Reopen Mozilla

Actual: A user can login to the system
Expected: Only permitted users should be able to login to the system