The Multipass tutorial is outdated

**Description of documentation issue or suggestion**
The [Multipass tutorial](https://documentation.ubuntu.com/multipass/latest/tutorial/) is pretty outdated. Images still show the old GUI, with options that are no longer available on the tray (e.g. "open shell").

**Proposal to fix issue or enact suggestion**
Revise tutorial end-to-end with contemporary information.
