Is it possible to get URL of workflow for the purpose of forwarding webhooks?

One of my Capybara tests involves filling out a Stripe Checkout and then testing that my app responds correctly to the checkout.session.completed webhook from stripe.
Locally it is possible to make this work with the Stripe CLI listen --forward-to flag.

Any suggestions? This is for a Rails project.
I could possibly use something like Ngrok?
Is is possible to get the URL of a workflow so I can forward webhooks to it?

Thank you.