Still part of b/454947209, removing references to WHOIS where we can. We
keep the registrar type and the column names (at least for now) because
changing those is much more complicated.
This is necessary because we'll use primary-contact emails as a way of
resetting passwords.
In the UI, don't allow editing of email address for primary contacts,
and don't allow addition/removal of the primary contact field
post-creation.
In the backend, make sure that all emails previously added still exist.
Pavlo TkachandGitHub
gbrodmanandGitHub