[FIX] l10n_ch: remove duplicated translation

A term was present twice in Italian, making the installation of
Italian crash for the Swich CoA
Introduced at a3029a8c

Remove some reference to company accounts (it is handled by
l10n_multilang, should not be set manually as working only for company
wiht id 1)

closes odoo/odoo#54658

X-original-commit: fb10cc6d
Signed-off-by: Martin Trigaux (mat) <mat@odoo.com>