微信小程序：Error: Behaviors should be constructed with Behavior()
使用了微信小程序计算属性 computed
const computedBehavior = require('miniprogram-computed')
报错
Error: Behaviors should be constructed with Behavior()
原来是版本更新了，没有改文档，需要按照新的方式引用
const computedBehavior = require('miniprogram-computed').behavior
[有bug] 微信文档：https://developers.weixin.qq.com/miniprogram/dev/extended/utils/computed.html
[推荐] NPM文档：https://www.npmjs.com/package/miniprogram-computed
