feat: 数据源面板插件支持数据mock

[jcljcljcl]

我们实际项目中需要用到数据源mock能力，开启mock开关后可在下方输入mock内容，目前简单利用input实现，后续可以加json编辑器，mock之后数据源中会存在isMock属性和相关mock数据。 我们目前重写了数据源的requestHandle函数对mock数据进行处理，用法不限于此。

[CLAassistant]

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[jcljcljcl]

@xingmolu 辛苦老板看一下哈

[liujuping]

@jcljcljcl 需要签一下 CLA

[jcljcljcl]

@liujupin

done

[liujuping]

@jcljcljcl 显示没有签成功，应该是 commit 的信息不对。

[liujuping]

由于CLA没有成功签署，这个 PR 先关闭，有需要再重新打开。