Feedback for docs/tutorials/get-started-with-ngo.md

[codercurtis]

In the subheading: "Test the RPCs", it says that you can also use Multiplayer Play Mode to test functionality.

1. The link is broken: https://docs-multiplayer.unity3d.com/tools/current/mppm

2. Nothing explains how you can use Multiplayer Play Mode to test this functionality

I gather from the suggested way, using a command line helper, you're supposed to start up a server/host and client, but there seems to be no documentation as to how that's supposed to work in MPPM.

The way that you can do it is to:

1. add a virtual player,
2. hit Play in the main window
3. In the virtual player window, edit the Layout so that you can see the Hierarchy and Inspector.
4. In the main editor window, select the NetworkManager and "Start Host/Server".
5. In the virtual player window, select the NetworkManager and "Start Client" in the inspector

Either this information should be included somewhere, or this hint could be moved to the end of the section to prevent confusion.