Add pagination section to API docs

[2color]

What

In a similar fashion to how we have a Filtering section, we should add a section on pagination.

Why

• The API has changed for before and after which now accept *WhereUniqueInput, e.g. UserWhereUniqueInput instead of a string.
• It can be used to enable pagination based on arbitrary uniques.

Example

Before:

const paginatedPosts3 = await prisma.post.findMany({
  first: 5,
  after: 43834,
})

After:

const paginatedPosts3 = await prisma.post.findMany({
  first: 5,
  after: { id: 43834},
})

[mhwelander]

Pagination pull request merged: https://www.prisma.io/docs/reference/tools-and-interfaces/prisma-client/pagination