Emulator: Unlink password auth provider removes email address from user

### Operating System

macOS

### Environment (if applicable)

web

### Firebase SDK Version

firebase@12.12.1

### Firebase SDK Product(s)

Firestore, Auth

### Project Tooling

Vue webapp

### Detailed Problem Description

In emulator when I call `firebase.auth().currentUser?.unlink('password')` the user email is removed from the emulator auth user. This behaviour is different from the online firebase auth.

### Steps and code to reproduce issue

in emulator:
1. register user with username + pw
2. connect google account
3. unlink password `firebase.auth().currentUser?.unlink('password')`