[DOCS] Documentation for from_hub to UI

[burtenshaw]

The from hub feature will soon return a link to UI on completion. This will mean there are four routes out of that method:

• automatically to the UI
• based on configuration files to server
• based on rg.Settings to the server
• inferred based on datasets.Features

This is complicated and requires attention in documentation. I would suggest we do this:

• [ ] update documentation page in hub documentation
• [ ] update existing how to guide in argilla on 'exporting' docs with latest changes
• [ ] add to quickstart guide with SDK into UI based entrypoint to argilla