[IMP] doc: warn user about the need to update
[IMP] doc: warn user about the need to update

Easy mistake for new developers

Courtesy of Pieczynski Marcin
Inspired by and closes #17959

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