fix(valine): attribute configurations do not take effect

[LyonUp]

What kind of change does this PR introduce? (check one with "x")

• Bug fix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

Does this PR introduce a breaking change? (check one with "x")

• Yes
• No

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Description

无法设置 valine 评论的 valine_notify/valine_verify 属性为 true ，因为在 javascript 中：

'true' == true; // return false

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Verification steps

在主题配置文件中：

comment:
    use: valine
    valine_notify: true # valine mail notify (true/false) https://github.com/xCss/Valine/wiki
    valine_verify: true # valine verify code (true/false)