Logged in admins do not lose admin status when it is changed + deleted users aren't kicked out

[qy21gafy]

Describe the bug
When an admin removes the admin status of itself, the status does not update until he logs out and logs in again. This also happens when an admin updates the status of another admin that is currently still logged in -> could pose large security problem. Deleted user's also aren't kicked out and can still book desks.

To Reproduce
Steps to reproduce the behavior:

1. Go to user management overview as an admin using the production server
2. Click on the admin checkbox of the logged in admin
3. The admin should now no longer be an admin and should not be able to access the user management page
4. However the logged in user can now just reclaim his admin priviledges

Expected behavior
The change in admin status should immediately change so that logged in previous admins can not just reclaim their admin status immediately. Deleted user's should also be kicked out when their account is deleted.

Screenshots
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Desktop (please complete the following information):

• OS: Windows 10
• Browser: Chrome
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: -
• OS: -
• Browser: -
• Version: -

Additional context
Add any other context about the problem here.

[xilef45]

That actually works. He only has to login again. So he can undo this action.

[jantiegges]

One can not change it's own access rights