create an option in kardinal dashboard to just print the URL rather than opening it

[galenmarchetti]

in codespaces, kardinal dashboard doesn't work because of the auto-open functionality. however, it would be very useful in the trying-out process to have a cleaner way to get the URL of the dashboard, something other than:

    echo "https://app.kardinal.dev/$(cat ~/.local/share/kardinal/fk-tenant-uuid)/traffic-configuration"

i'd suggest something like kardinal dashboard --url or something to just print it rather than open it