During the formating method, the country code
was compared to the country phone code. Indeed,
phonenumbers python lib return a `PhoneNumber`
object having a `country_code` attribute
refering to the country_phone_code, and not
the country_code (like odoo means).
Consequence: changing the country on a lead
did not make the phone validation work.
Thus, it was required to give both code (country
and country phone codes) to the phonenumbers API,
in order to make a correct verification.