fix: 商品规格添加成本计算错误

src/views/business/goods/components/spec.vue

@@ -154,7 +154,7 @@ export default {
       this.specListTmp = JSON.parse(JSON.stringify(this.specList))
       this.skuList = sku.map(item => {
         this.$set(item, 'valueY', accDiv(item.value, 100))
-        this.$set(item, 'costY', item.cost == '' ? '' : accMul(item.cost, 100) )
+        this.$set(item, 'costY', item.cost == null ? '' : accDiv(item.cost, 100) )
         this.$set(item, 'picUrlArr', item.picUrl.split(',').map(item => { return { fileName: item }}))
         this.$set(item, 'status', !!item.quantity)
         return item