(To eliminate) For the time being, eliminate de Autentificare button and the Profesionist user type

Currently and for the first version of the platform, the only user types are: SuperAdmin, Simple Admin and Visitor. The admins can log in through /admin on the slug, so they do not need the button. If other types of users will be added in the future, they will be adjusted accordingly, however as of right now it will only create confusion + add expectations for functionalities we did not initially plan for.

So the Autentificare button should disappear, as well as the Profesionist user type.