Web sequences don't seem to be supported

Web sequences seemingly always return:

```json
{"error":"The requested resource does not exist."}
```

This is because in the plugin today, for web actions we only invoke if there is no sequence found. See https://github.com/adobe/aio-cli-plugin-app-dev/blob/main/src/lib/run-dev.js#L525

I am not sure if this is a bug or an intentional thing, but documenting this issue so its known

首先阅读第 525 行附近的 src/lib/run-dev.js，并重现 web 序列的报告响应。确定当前条件是有意为之还是一个 bug，然后验证预期的 web 序列行为已经确立，并且已处理或记录报告的结果 "requested resource does not exist"。

由索引模型根据 Issue 内容生成。