Change sass-loader plugin path

[naupaw]

url path https://deno.land/x/aleph@0.2.19/plugins/sass.ts seems not working and making confusion for new comer , either change to latest version of sass plugin or stick with current version with url below.

https://deno.land/x/aleph@v0.2.19/plugins/sass.ts

[vercel[bot]]

This pull request is being automatically deployed with Vercel (learn more).
To see the status of your deployment, click below or on the icon next to each commit.

🔍 Inspect: https://vercel.com/postui/alephjs/d6h1ksqm0
✅ Preview: https://alephjs-git-fix-sass-docs.postui.vercel.app

[ije]

looks great, thanks @pedox !