Installer app not shown for spoofed com.android.vending

### Please check before submitting an issue

- [x] I know what my device, OS and App Manager versions are
- [x] I know how to take logs
- [x] I know how to reproduce the issue which may not be specific to my device

### Describe the bug

The "Installer app" field isn't shown for spoofed `com.android.vending`.

Though it's probably in the literal installer part of AM, not the app info viewer:
```console
$ su -c pm list packages -i com.bereal.ft
package:com.bereal.ft installer=null
```

### To Reproduce

1. Use Aurora Store with the App Manager install method
2. Begin installing any app
3. In the AM installer popup, select the installer app to be Google Play Store
4. Finish installing the app, and click on "App Info"
5. The "Installer app" field doesn't show up
6. Select YouTube in AM; "Installer app" shows Google Play Store as the "Installer" and the "Actual installer"

Seems that Aurora Store also fails to set the installer:
1. Use Aurora Store with the root install method
2. Install any app
3. Check it in AM
4. No "Installer app" field

### Expected behavior

It should show up. I expect the "Actual installer" field to show App Manager, but still.

### Screenshots

_No response_

### Logs

_No response_

### Device info

- Device: OnePlus Nord CE 5G (ebba)
- OS Version: Android 13/OxygenOS 13
- App Manager Version: 4.0.5
- Mode: Root

### Additional context

_No response_