[fix] 一次性回购设置支付频率为空，支付期数为1

src/main/webapp/modules/cont/CON_REPO001/con_contract_change_repo_detail.lview

@@ -84,6 +84,7 @@
                     record.getField('payment_period').setReadOnly(true);
                     record.set('payment_period', 1);
                     record.set('payment_frequency', '');
+                    record.set('payment_frequency_n', '');
                     if (name == 'ccr_due_amount') {
                         var due_amount = record.get('due_amount') || 0;
                         if (due_amount < value) {