docs: fix imports of cheerio in examples

[B4nan]

Related: #661

[B4nan]

cc @metalwarrior665, I've left only one occurence of the named import (import {load} from 'cheerio') as it was described in that specific section, so it felt fine, but we might wanna change that too.

https://docs.apify.com/academy/puppeteer-playwright/executing-scripts/collecting-data#parsing-in-node-context

[barjin]

There is a bunch of other places where the Cheerio imports are unused(?), I would vote for removing those altogether