Add GitLab map to the docs

What does this MR do?

Add the GitLab map to the docs inside the UI guide. Also removed a line that said the GitLab logo and the user picture show up in the sidebar because they don't any more.

What are the relevant issue numbers?

#19350 (closed)

• CHANGELOG entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the style guides
• Branch has no merge conflicts with master (if you do - rebase it please)
• Squashed related commits together Closes #19350 (closed)