Promote logics in auth::authentication::Authenticate to a public api, which unfortunately cannot be the same due to the inconsistent naming, hence we have to create a new alias
Rationale:
- the proc provides some value to the user by choosing the right contract implementation depending on the authority
- we found occurrences in other packages downstream, and as internally this proc is calling only public api, one could just duplicate the whole thing and be compliant with our standards, which is not an improvement IMO
- the proc was already tested and documented