[FIX] mail: assert email field used in blacklist and correctly use it in computed fields
[FIX] mail: assert email field used in blacklist and correctly use it in computed fields

This commits fixes the use of email field in blacklist mixin as it was based
on 'email' field instead of the one coming from the _primary_email class
attribute since commit 2ff9b379ef80ba6a8744fb9702a8088284372ddd.

This commit is related to task ID 33224 (original blacklist implementation
done for v12) and its PR #25966 as well as task ID 1889703 (tests and fixes)
and its PR #27330. Done with collaboration of @dbeguin.

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo