text: Title: [feat] Without public home page, a 404 error is raised
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  ### Summary
  
  If a root page has been created, but is not public (e.g., with djangocms-versioning), a 404 error is raised when the user tries to visit the root page.
  
  While technically correct, a better user experience can be achieved by **redirecting the user to the page tree**. This is comparable with the user being redirected to a welcome page when no page object is present at all. 
  
  ### Expected behaviour
  
  Either show the welcome page with an explanation (page has been created but is not public) or redirect to the `PageContent`'s changelist in the admin which shows the page tree and allows actions like preview or publish.
  
  
  ### Actual behaviour
  
  404
  
  ### Environment
  
  * django CMS version: 4.1.0
  