Example of how to use firebase.createUserWithEmailAndPassword()?

I've tried mocking the
```js
firebase.auth()
```
object as well as the XHR requests firebase makes with `cy.request()` but haven't had any luck - do you have an example of mocking user creationg with `firebase.auth().createUserWithEmailAndPassword()`?

Start by reviewing the repository's existing Cypress and Firebase authentication example and the reported mocking approaches using firebase.auth() and cy.request(). Add a working example for mocking createUserWithEmailAndPassword(), with documentation showing how to use it from a Cypress test.

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