There are 2 ways to unregister a service worker:

Programmatically unregister

You call getRegistrations() method of navigator.serviceWorker object. The method returns a Promise that resolves to an array of registrations.

Each of the registration objects has an unregister() method.

navigator.serviceWorker.getRegistrations().then(function(registrations) {
 for(const registration of registrations) {
  registration.unregister()
} })

Through the user interface

You can unregister the service worker in the Service Workers section of the Application tab in Chrome Devtools