[FIX] l10n_it_edi: demo data from US gets an Italian VAT number

Fixing some demo data from US having an Italian VAT.
Also, a partner's name and VAT has been changed not to be too similar
to one of our actual clients. Now the Engie Italia's VAT is used.

closes odoo/odoo#102904

Signed-off-by: Josse Colpaert <jco@odoo.com>