currently the returned warning from the sale, stock and repair apps are not translatable to user languages. this pr makes the string's translatable and correct the grammer of the warning. closes odoo/odoo#108379 X-original-commit: 217115e68d117d7cf1eeb94794118819d6082547 Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>