Formdata Spanish accents or other special characters don't show up as one would expect

Describe the bug

When creating fomData with name fields with accents such as the word “Género”, when parsing in the server it shows up as garbled text such as “Género”. I believe the the behavior would be that it would show up as “Género”, but please correct me if I am wrong.

Reproduction

Link to the reproduction below in the following repo: https://github.com/luthfib/sveltekit-bug-repro. I created a minimal sveltekit repo that has two input fields and a submit button using use:enhance. Once the data is submitted I have. validate action that receives it and upon inspecting the data in the server it can be seen that the characters are not encoded as one would expect.

Logs

No response

System Info

System:
    OS: macOS 13.0.1
    CPU: (8) arm64 Apple M1 Pro
    Memory: 98.81 MB / 16.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 18.4.0 - ~/.nvm/versions/node/v18.4.0/bin/node
    npm: 8.13.2 - ~/.nvm/versions/node/v18.4.0/bin/npm
  Browsers:
    Brave Browser: 98.1.35.101
    Chrome: 107.0.5304.110
    Firefox: 107.0
    Safari: 16.1
  npmPackages:
    @sveltejs/adapter-auto: next => 1.0.0-next.89 
    @sveltejs/kit: next => 1.0.0-next.563 
    svelte: ^3.44.0 => 3.53.1 
    vite: ^3.1.0 => 3.2.4

Severity

annoyance

Additional Information

No response

[repsac-by]

https://github.com/nodejs/undici/pull/1786

[Conduitry]

@sveltejs/kit@1.0.0-next.575 include the update to undici@5.14.0, so this should be fixed now.