file upload not work

[nstp]

• REST Client Version: v0.25.1
• VSCode Version: 1.85.1
• OS Version: Windows_NT x64 10.0.22621

Steps to Reproduce:

1. Create Request:

   
   POST http://{{url}}
   Content-Type: multipart/form-data; boundary=TestBoundary

--TestBoundary Content-Disposition: form-data; name="test.trace"; filename="test.trace" Content-Type: application/octet-stream < ../trace/test.trace --TestBoundary--

2. Send Request:
    vscode pop out an error info "Cannot read properties of undefined (reading 'flowing')"
![image](https://github.com/Huachao/vscode-restclient/assets/29659537/ef9d5d6e-36ac-46bc-ab9d-7aa5e2c4dddd)

[tertek]

@Huachao I can confirm that file upload seem not to work with some file types.

I have tested your examples from the documentation with a .xml and .png.

In case of xml it works fine.

In case of .png the file is not being attached. I have tested the very same http request with Postman, which works on my locally hosted API.

Also tried relative/absolute paths without effect.