Fix typo in dev branch, app dev part. Update delete-data.md

[shawn0915]

fix typo for table ratings and column rated_at.

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[ti-chi-bot]

@shawn0915: PR needs rebase.

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[Icemap]

非常抱歉 @shawn0915 ，非常棒的 PR，但是它落后了当前分支太多，而且这部分的文档变更涉及到示例代码的变更，同时还需中英文文档同步。因此我会关闭它。
非常感谢您的贡献。祝好。

另附此 PR 的相关链接：

• 替代此 PR 的英文文档 PR：[Debug] outdated code and table name docs#8889
• 替代此 PR 的中文文档 PR：[Debug] outdated code and table name #9766
• 需与文档保持一致的示例 Java 代码仓库：https://github.com/pingcap-inc/tidb-example-java
• 需与文档保持一致的示例 Golang 代码仓库：https://github.com/pingcap-inc/tidb-example-golang