docs: index fluid style pattern

[francinelucca]

Related #carbon-design-system/carbon-platform#1607

Testing / Reviewing

Replace carbon-styles key in devLibraries object in services/web-app/data/libraries.mjs file of your local clone of Carbon Platform with:

'carbon-styles': {
    host: 'github.com',
    org: 'francinelucca',
    repo: 'carbon',
    path: '/packages/styles',
    maintainer: 'carbon',
    group: carbonComponentsGroup,
    ref: 'index-fluid-styles-pattern'
  }

Then run web-app, you should see the new pattern in the index

[netlify]

✅ Deploy Preview for carbon-components-react ready!

Built without sensitive environment variables

Name	Link
🔨 Latest commit	bb2277f
🔍 Latest deploy log	https://app.netlify.com/sites/carbon-components-react/deploys/6434a1bc074ac000088e00b7
😎 Deploy Preview	https://deploy-preview-13296--carbon-components-react.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site settings.

[netlify]

✅ Deploy Preview for carbon-elements ready!

Name	Link
🔨 Latest commit	bb2277f
🔍 Latest deploy log	https://app.netlify.com/sites/carbon-elements/deploys/6434a1bcda652d0008bc3efb
😎 Deploy Preview	https://deploy-preview-13296--carbon-elements.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site settings.