feat(PPDSC-2175): layout props 7/7

[evgenitsn]

PPDSC-2175

What

added

• margin and padding logical props support
• storybook scenarios
• updated docs

for the following components:

• Heading
• Paragraph
• Unordered List
• Video Player

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-2175-layout-props-7
Storybook: http://ncu-newskit-docs.s3-website-eu-west-1.amazonaws.com/ppdsc-2175-layout-props-7/storybook

[Xin00163]

This looks good. I am just a bit lost on why we have margin: 0 in heading in the first place and if there is any impact.

Got it: It's to reset the browser default margin for <p> tag: https://stackoverflow.com/questions/20850594/what-is-the-default-margin-value-of-p-tag