[Pagination, PaginationNav] update Usage docs

[laurenmrice]

Ref original issue: #3238
Ref boxnote: Usage tab PDF a11y comments

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Acceptance criteria

• Update the pagination component Usage tab documentation with the new content template.
• Add pagination nav as another variant.
• Look at Michael Gowers A11y PDF review and resolve any open questions and suggestions.

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Things to address in the current docs

Most of the A11y considerations were that we have not updated out docs with the new content template. Below are some other comments:

Overview

• Are there exceptions of not displaying pagination if there are more than 25 pages/items of content? (I have removed this guidance because I feel that pagination can be used for different reasons and there is some more nuance than suggesting 25 pages/item is the rule)
• What are the different contexts of where pagination is used?

Best practices

• The labeling of the pagination sections could be improved a11y wise. This will need to be updated in code first before changing them here in the docs. I have made a separate issue for this in the mono repo which we need to further refine and tackle [Pagination]: improve order of select labeling for screen readers carbon#16538

• Add a section for "Responsiveness" and how the pagination content should change and respond depending on the breakpoint. Only pertinent information should remain in the pagination component at smaller breakpoints.

[thyhmdo]

Roll over the next sprint. The effort seems right, the main goal for rollover is to review.