Fix removing access to a user on its personal workspace

• Remove all permissions for user "toto" on his personal workspace
• Login as "toto"

=> An error is thrown, user is blocked
=> Nothing appears in the logs
=> Putting the "Everything" permission is the only way to get a normal behaviour back
=> This can be a security issue if you allow anonymous access, because you can't remove the everything right on the Guest's personal workspace, and then anybody can create anything in the platform in this space

This behavior cannot be reproduced in 6.0