docs(PPDSC-2259): skeleton of homepage

[Xin00163]

PPDSC-2259

This is a small ticket to lay out the build the skeleton of the homepage. Each section is currently being occupied by a placeholder.

To review please visit:
http://ncu-newskit-docs.s3-website-eu-west-1.amazonaws.com/ppdsc-2259-homepage-gridlayout/index-new

I have done:

• Written unit tests against changes
• Written functional tests against the component and/or NewsKit site
• Updated relevant documentation

I have tested manually:

• The feature's functionality is working as expected on Chrome, Firefox, Safari and Edge
• The screen reader reads and flows through the elements as expected.
• There are no new errors in the browser console coming from this PR.
• When visual test is not added, it renders correctly on different browsers and mobile viewports (Safari, Firefox, small mobile viewport, tablet)
• The Playground feature is working as expected

Before:

After:

Who should review this PR:

How to test:

[newskit-engineering]

You can preview these changes on:
Documentation Site: http://ncu-newskit-docs.s3-website-eu-west-1.amazonaws.com/ppdsc-2259-homepage-gridlayout
Storybook: http://ncu-newskit-docs.s3-website-eu-west-1.amazonaws.com/ppdsc-2259-homepage-gridlayout/storybook

[Srinivasan-Ramasamy]

Looks good 👍