AuthenticationTestBase should not extend EntityShareClientFunctionalTestBase

Problem/Motivation

AuthenticationTestBase and so all the authentication tests are extending from this common base class.

This is bringing in FAR too much stuff! e.g.:

> Unable to install modules: module 'entity_share_test' is missing its dependency module block_field.

Why is a test for authentication trying to install block_field? Or even entity_share_test and all its config?

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes