Improve Geo database setup manual

What does this MR do?

This change fixes three problems:

• I'm not necessarily using UNIX like OS as a local machine, so we don't have to force a user to use scp
• It's common to authenticate to server as a non-root user and then use sudo -i, so when we recommend running scp server.crt secondary.geo.example.com: we copy to /home/non-root/ rather then /root/ as the next step expects it to be.
• Fix a minor TYPO I introduced yesterday.

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• Internationalization required/considered
• If paid feature, have we considered GitLab.com plan and how it works for groups and is there a design for promoting it to users who aren't on the correct plan
• End-to-end tests pass (package-qa manual pipeline job)

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