Add ai68298100/siyuan-exam

[ai68298100]

请确认以下信息：

1. 不涉及侵权内容，例如无商用授权的字体。
   已检查本次发行包，未发现未经授权的第三方内容；包内不包含商业题库或字体文件。
2. 如果集市包是闭源的，请创建一个包含集市包完整源代码的私有 GitHub 仓库，并授予 @TCOTC、@88250 和 @Vanessa219 仓库访问权限，以便我们完成审核。
   本插件为开源项目，完整源代码已在下方公开仓库中，无需私有审核仓库。

仓库：https://github.com/ai68298100/siyuan-exam

[TCOTC]

插件加载或者点击顶栏按钮之后报错：

Uncaught (in promise) TypeError: Converting circular structure to JSON
    --> starting at object with constructor 'na'
    |     property 'plugins' -> object with constructor 'Array'
    |     index 0 -> object with constructor 'PluginSnippets'
    --- property 'app' closes the circle
    at JSON.stringify (<anonymous>)
    at common.a8041652632a36a13450.js:2479:15368
    at Array.forEach (<anonymous>)
    at fe (common.a8041652632a36a13450.js:2479:15287)
    at B (common.a8041652632a36a13450.js:5422:5014)
    at iK.openTabByType (plugin:siyuan-exam:285:1811)
    at iK.openPractice (plugin:siyuan-exam:285:5752)
    at HTMLDivElement.callback (plugin:siyuan-exam:271:5256)

[github-actions]

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新增插件仓库 / Add Plugin Repo

ai68298100/siyuan-exam

最新 Release / Latest Release: v0.9.5

检查通过。

Check passed.

_{在思源中试用本次 Release / Try this Release in SiYuan}

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[github-actions]

感谢你的贡献，思源有你更精彩！
Thank you for your contribution. SiYuan will be more wonderful with you!