[Bug] firebase doesn't select app by package name

### Description

when google-services.json contains more than 1 app, firebase doesn't choose app base on package name, it always choose one of apps no matter what package name.

### Reproducing the issue

- create an empty firebase project
- create 2 android apps with 2 different package name (1) and (2)
- create an empty unity project with package name (1)
- download google-services.json and place into unity project
- log Debug.LogError(FirebaseApp.DefaultInstance.Options.AppId); in script
- build apk (1)
- change package name to (2)
- build apk (2)
- run apk (1) => logcat will show appId of app (1)
- run apk (2) => logcat will show appId of app (1)

### Firebase Unity SDK Version

12.1.0

### Unity editor version

2022.3.17

### Installation Method

Unity Package Manager

### Problematic Firebase Component(s)

_No response_

### Other Firebase Component(s) in use

_No response_

### Additional SDKs you are using

_No response_

### Targeted Platform(s)

Android

### Unity editor platform

Windows

### Scripting Runtime

Mono

### Release Distribution Type

Pre-built SDK from https://firebase.google.com/download/unity

### Relevant Log Output

_No response_

### If using CocoaPods for Apple platforms, the project's Podfile.lock

Expand Podfile.lock snippet

```yml

👀 Replace this line with the contents of your Podfile.lock!

```

Reproduce the issue in the Unity Android project using two apps and the provided google-services.json, then trace the SDK path that selects the Firebase app by package name. Done means builds with package names (1) and (2) log the corresponding AppId instead of always selecting app (1).

Written by the indexing model from the issue text.