Remove references to first VwG EAP.

[brnnmrls]

Removes references to the first EAP. These changes include three major items:

1. Remove references within our classes, like GIDRestrictedScopesRegistry and GIDVerifiableAccountDetail.
2. Remove references within the tests, like GIDRestrictedScopesRegistry, GIDSignInInternalOptionsTest, GIDSignInTest, GIDVerifiableAccountDetailTest, GIDVerifiableAccountDetailResultTest, and GIDVerifyAccountDetailTest.
3. Remove example from DaysUntilBirthday sample app completely.
4. Fix failing tests in DaysUntilBirthdayUITests_iOS.swift to cover new header text.