Upgrade Sass

[MetRonnie]

Supersedes #1975, fixes the deprecation warnings it brings

If you're using Vite in your application try replacing sass (legacy) with sass-embedded (modern): https://vuetifyjs.com/en/features/sass-variables/#build-performance

https://github.com/vuetifyjs/vuetify/issues/20489#issuecomment-2358897408

Check List

• [x] I have read CONTRIBUTING.md and added my name as a Code Contributor.
• [x] Contains logically grouped changes (else tidy your branch by rebase).
• [x] Does not contain off-topic changes (use other PRs for other changes).
• [x] No stuff needed
• [x] If this is a bug fix, PR should be raised against the relevant ?.?.x branch.