feat(next-css): Support extra options for extract-css-chunks-webpack

[Djiit]

Hi there,
What's going on here :

• Updated extract-css-chunks-webpack-plugin to. v4.5.6 ;
• Passed down extractCssOptions from nextConfig to the webpack plugin constructor;

What needs to be done :

• Add something in next-css and next-sass README.md
• Arrange each package's version so they benefits from this upgrade (I don't know how you manage it here)

Happy to discuss !

[Djiit]

Hey @timneutkens did you have a chance to review this ? It would greatly benefit the dev experience. Thanks!

[timneutkens]

I'm going to close this in favor of vercel/next.js#8626

Thanks for your contribution 🙏