space is added after comma in data uris in srcsets

[riw]

Describe the bug

when a data uri of the form 'data:image/svg+xml;utf8,...' is used in srcsets vite adds a space after the comma like 'data:image/svg+xml;utf8, ...'

Reproduction

https://stackblitz.com/edit/vitejs-vite-ykknzg?file=index.html

Steps to reproduce

No response

System Info

System:
    OS: macOS 14.6.1
    CPU: (12) arm64 Apple M2 Max
    Memory: 179.67 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.15.1 - ~/.nvm/versions/node/v20.15.1/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 10.7.0 - ~/.nvm/versions/node/v20.15.1/bin/npm
    pnpm: 8.6.2 - ~/Library/pnpm/pnpm
  Browsers:
    Chrome: 130.0.6723.59
    Safari: 17.6
  npmPackages:
    vite: ~6.0.0-beta.2 => 6.0.0-beta.2

Used Package Manager

npm

Logs

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to vuejs/core instead.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[sapphi-red]

This is already fixed by #18242. It is released since 6.0.0-beta.3.