fix: 销售订单新增无客户性订单，添加对客户partaId存在性检查避免空值错误

src/views/saleManage/saleOrder/components/addDialog.vue

@@ -1693,7 +1693,9 @@
         API(commitData)
           .then((res) => {
             this.loading = false;
-            updateRelationStatus([this.form.partaId]);
+            if(this.form.partaId) {
+              updateRelationStatus([this.form.partaId]);
+            }
             if (this.form.contractId) {
               updateContractStatus([this.form.contractId]);
             }