feat(doc): 'html', 'adoc', 'doc' should support 'Example' just as 'markdown'

[jasonkung22]

1. 'html' document support 'Example' fields
2. 'adoc' document support 'Example' fields
3. 'doc' document support 'Example' fields
4. Fix the adoc document request header parameters are incorrect

Closes #984

[github-actions]

Thanks for your this PR. 🙏
Please check again for your PR changes whether contains any usage configuration change such as Add new configuration, Change default value of configuration.
If so, please add or update documents(markdown type) in docs/ for repository smart-doc-group/smart-doc-group.github.io

In addition, if you have added new features, please provide example code in the repository smart-doc-group/smart-doc-example-cn. This will help other users understand how to use the new features.

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感谢您提交的PR。 🙏
请再次查看您的PR内容，确认是否包含任何使用方式 配置参数的变更，如：新增配置参数、修改默认配置等操作。
如果是，请确保在提交之前，在仓库smart-doc-group/smart-doc-group.github.io中的docs/目录下添加或更新文档（markdown格式）。

另外，如果您添加了新功能，请在仓库smart-doc-group/smart-doc-example-cn中提供示例代码。这将帮助其他用户了解如何使用新功能。