setting languageCode does not impact template language. Emails are sent using default language specified in Firebase console

### Version info

**Angular:**
15.0.0

**Firebase:**
"version": "9.14.0",

**AngularFire:**
"@angular/fire": "^7.5.0",

### How to reproduce these conditions

**Failing test unit, Stackblitz demonstrating the problem**

**Steps to set up and reproduce**

this.afAuth.languageCode = Promise.resolve('de');
await this.afAuth.sendPasswordResetEmail(passwordResetEmail);

### Expected behavior

Should sent email with defined language

### Actual behavior

Sending an emil with defined language in Firebase console: [Screenshot 2022-11-30 at 11 15 18](https://user-images.githubusercontent.com/3918999/204769562-7887d107-6430-4ed0-a365-f57aa2ce8afb.png)

Detailed explanation:

I am still facing this issue... this.afAuth.languageCode = Promise.resolve(lang); still sends emails with default template language set in firebase console.

any solution anyone?

p.s. I do:

```
this.afAuth.languageCode = Promise.resolve('de');
await this.afAuth.sendPasswordResetEmail(passwordResetEmail);
```

首先使用 Angular 15、Firebase 9.14.0 和 @angular/fire 7.5.0 重現此問題，先進行 languageCode 指派，再呼叫 sendPasswordResetEmail。追蹤 languageCode 如何透過該呼叫傳遞，並將要求的語言與 Firebase Console 中的範本設定進行比較。當密碼重設電子郵件使用透過 languageCode 提供的語言，且有回歸測試或記錄在案的限制涵蓋此行為時，即視為完成。

由索引模型根據 Issue 內容生成。