[Bug]: Origin tauri://localhost is not allowed by Access-Control-Allow-Origin. Status code: 204

### What happened?

I get a CORS error when I send an HTTP request (same error from browser or Node.js).

```
[Error] Origin tauri://localhost is not allowed by Access-Control-Allow-Origin. Status code: 204
[Error] Fetch API cannot load https://api-prod.omnivore.app/api/graphql due to access control checks.
```

The same query works from Postman and curl.

The server probably rejects "origin: tauri://localhost".

(I tested with https://mockbin.com that this is not this bug: https://github.com/tauri-apps/tauri/issues/2327);

See also https://github.com/Ironclad/rivet/issues/28

### What was the expected functionality?

HTTP

### Describe your environment

Kubuntu 23.04
rivet_1.2.1_amd64.AppImage

### Relevant log output

_No response_

### Relevant screenshots

_No response_

### Code of Conduct

- [X] I agree to follow this project's Code of Conduct