I added field named cashier_name to pos order line and i need to show it in sale report
i added the same field to sale.report , but when i pass the value to sale report by _query function it doesn't work   odoo15

class SaleReport(models.Model):
    _inherit = "sale.report"

    cashier_name = fields.Char(string='Employee', readonly=True)

    def _query(self, with_clause='', fields=None, groupby='', from_clause=''):
        fields['cashier_name'] = ",l.cashier_name"
        return super()._query(with_clause, fields, groupby, from_clause)