Random URL on deploying azure static web app
Yes, by default Azure Static Web App
auto-generates domain URL.
The option available to access the Static WebApp with another URL is to Configure a new Custom domain
.
You can see MSDoc mentions the same.
By default, Azure Static Web Apps provides an auto-generated domain name for your website, but you can point a custom domain to your site.
Even if we configure the custom domain, the auto-generated URL
cannot be changed, just a new domain is added in the Custom domain
section.

Refer MSDoc to Configure custom domain for Azure Static WebApp
.***
I have observed that the auto-generated URL name is same as the workflow file last name.
Ex:
URL - https://orange-smoke-099cdb110.2.azurestaticapps.net
Workflow name - azure-static-web-apps-orange-smoke-099cdb110.yml
I have tried to change the yml
file name and run the job again. Unable to change it.