Drupal 11 / CMS documentation link to backup and restore

Moving to Drupal CMS project and assigning to Documentation track.

This actually needs to be in Automatic Updates, which is where that text originates.

I came across this link as well when working on 📌 Add documentation section for automatic updates Active and agree that the page it links to is not ideal. I started drafting some content about making backups for Drupal CMS in this document https://docs.google.com/document/d/1_0Qt3nJJ_cprowSXrA3nGKdGC27_TE6UIZWi....

Originally I was thinking that page would be in the Drupal CMS guide, but since automatic updates is part of Drupal core, and not Drupal CMS, I think it makes sense to have a page like the one currently linked on Drupal.org that isn't part of the Drupal CMS Guide that provides information for anyone using Drupal. Basically, an updated and improved version of the currently linked page https://www.drupal.org/docs/7/backing-up-and-migrating-a-site/backing-up... → . As well as a page in the Drupal CMS guide that points to that new/updated page and provides information about anything that's specific to backing up a Drupal CMS site.

Added 📌 Improve messaging to users to backup database Needs review as related issue.