Update requirements
Update requirements

Should fix tests which failed due to old Flask-Login versions fulfilling
requirements.txt

agdsn/pycroft,lukasjuhrich/pycroft,lukasjuhrich/pycroft,agdsn/pycroft,agdsn/pycroft,lukasjuhrich/pycroft,agdsn/pycroft,lukasjuhrich/pycroft,agdsn/pycroft