Can't find the function url for Firebase webhook in Google Assistant tutorial

I noticed you included the tag #actions-on-google in your question. I think perhaps Firebase does not print the URL for dialogflowFirebaseFulfillment actions. But, you can also view your functions' URLs inside the Firebase console.

If you don't know it already, you can get the console's URL from deploying. After deploying the console URL will be printed in the output as shown below. Note console URL does not change from deploy to deploy, so you can bookmark it as well.

Project Console: https://console.firebase.google.com/project/goodmorningroutine-ac4b1/overview

Inside the Firebase console go to Functions on the left. That page will show a list of functions each with its request URL as shown below.

When the codelab instructs you to run firebase deploy --only functions, it will output the URL for the HTTP function that you created. It will be the last line of output and look something like this:

Function URL (foo): https://us-central1-my-codelab.cloudfunctions.net/foo

Copy that URL - it's your webhook endpoint.

I was facing the same issue ..... I Just saved the file before deploying

That easy I hope it works for you