Fix <picture> sources not follow color scheme preference

[cscnk52]

This PR fix <picture> element not follow colorPreference, see my crate simpleicons-rs, it has a element in front of README, and I prepare two color pictures for it:

<picture>
  <source media="(prefers-color-scheme: dark)" srcset="https://github.com/cscnk52/simpleicons-rs/raw/refs/heads/main/assets/img/simpleicons-rs-banner-dark.png" />
  <source media="(prefers-color-scheme: light)" srcset="https://github.com/cscnk52/simpleicons-rs/raw/refs/heads/main/assets/img/simpleicons-rs-banner-light.png" />
  <img alt="simpleicons-rs banner" src="https://github.com/cscnk52/simpleicons-rs/raw/refs/heads/main/assets/img/simpleicons-rs-banner-light.png" />
</picture>

It should follow crates.io theme to change, but not.

After attach debug to it, I found just wrong order of colorPreference and input, just swap them to fix.

After fix, it looks good.

Related to a216b9f#diff-e24e30bcf8defc9f1a68733bae25f89198502daa94e3a20ae0dc4d5a8f971a3fL9-R9

[Turbo87]

huh, looks like this broke during #11734 :-/

thanks for the fix! :)