Fix unsuccessful token login logged as error

Fix unsuccessful token login logged as error

The condition of a non-existent login token can happen for concurrent
requests. Admins can not do anything about this. So this is to be
expected to happen occasionally. This event is only bad if none of the
requests is able to re-acquire a session. Luckily this happens rarely.

If a login loop persists an admin can still lower the log level to find
this info. But a default error log level will no longer write those
infos about the failed cookie login of one request.

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>