[bug] Unable to receive plain text data in the request body

### Search before asking

- [X] I had searched in the [issues](https://github.com/labring/laf/issues?q=is%3Aissue) and found no similar issues.

### Environment

https://laf.run

### What happened

When the data in the POST request body is plain text and 'Content-Type' is set to 'text/plain; charset=utf-8', no data can be retrieved from the query, headers, or body of the cloud function.

### How to reproduce

1、Use Postman to send a request to the cloud function, set 'Content-Type' to 'text/plain; charset=utf-8', enter plain text data in the request body, and finally send the request.
2、Check if the plain text data exists in the context of the cloud function.

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

Start by reproducing the request with Postman against a cloud function, using Content-Type text/plain; charset=utf-8 and a plain-text body. Trace how the cloud function receives request query, headers, and body data; done means the plain-text payload is available in the request context without breaking other request formats.

Written by the indexing model from the issue text.