Resolve "User Authentication"

See merge request swp-ws21-fahrtenbuch/team-einhorn/fahrtenbuch!14

Co-authored-by: Hanen Alrwasheda <NiToThePowerOf2Plus2@users.noreply.github.com>
Co-authored-by: Florian-Studium <Florian-Studium@users.noreply.github.com>

Co-authored-by: Hanen Alrwasheda <NiToThePowerOf2Plus2@users.noreply.github.com>
Co-authored-by: elkazelka <elkazelka@users.noreply.github.com>
Co-authored-by: mzeoba <mysuradze@gmail.com>