[Docs] Update spacing illustrations for sections and panels

[xak]

Some layout components need to be updated based on the new spacing specs

The new spacing specs changes the common, regular unit from 20px to 24px. The standard unit for paragraph and other margins is now 16px from 20px.

Detailed description

Describe in detail the issue you're having.

The spacing illustrations are out of date — https://sap.github.io/fundamental/foundation/spacing.html

[xak]

@LeoT7508 Can you take this for the upcoming release?

[saad-mo]

@LeoT7508 do you have an eta on the updated visuals?

[LeoT7508]

@saadmhybris

Updated visual aids.

Grid_V2.zip