The aim of this commit is to add a warning when an invoice is uploaded and a duplicate of this invoice already exists in db.
It is the same behaviour that we already have for vendor bills
Previous to this commit:
When uploading duplicate vendor bill -> Warning
When uploading duplicate invoice -> NO Warning
After this commit:
Warning in both cases
closesodoo/odoo#126096
Task: 3378169
Signed-off-by: Brice Bartoletti (bib) <bib@odoo.com>