A couple things.
First, you may need to change to the AtoM root directory first. We include both the AtoM code and the AtoM documentation in the Vagrant box. Try:
And then you can try running the command again.
Another note - it may be that something about how your terminal is wrapping the command to a new line is causing an issue, based on the error? Either that, or you can try not including the < > brackets around your username, and that may work better.
In any case, you can also try running the command without passing any parameters or options - AtoM will then walk you through selecting a username, email, and password. For example, if you just run:
- php symfony tools:add-superuser
Then here is the typical outcome:
Let us know if this helps!