Fix invalid translation file

[creekorful]

Fix invalid translation file which resulted in an HTTP 500 error when browsing the product list.

***.**.**.*** -  18/Nov/2025:10:43:50 +0100 "GET /product/list.php" 200
NOTICE: PHP message: PHP Fatal error:  Uncaught ValueError: Unknown format specifier ")" in /var/www/html/htdocs/core/class/translate.class.php:657
Stack trace:
#0 /var/www/html/htdocs/core/class/translate.class.php(657): sprintf('Taux de marque/...', '', '', '', '')
#1 /var/www/html/htdocs/core/class/html.form.class.php(8987): Translate->trans('DiscountRulesMi...')
#2 /var/www/html/htdocs/product/list.php(952): Form::multiSelectArrayWithCheckbox('selectedfields', Array, 'productlist', '1')
#3 {main}
  thrown in /var/www/html/htdocs/core/class/translate.class.php on line 657