Does not work in APK

## 🐛 Bug Report

Works great when running in the IDE on either an emulator or a physical device via USB but once APK has been built and distributed to any device via Firebase App Distribution, no images appear.

I have allowed INTERNET permissions in the manifest file so that is not the issue. Using a normal Network Image widget or a FadeInImage.assetNetwork widget works fine but this package does not work when deployed out via App Distribution.

Permissions added to the AndroidManifest.xml files:

### Expected behavior
To see images.

### Reproduction steps
Get the CachedNetworkImage widget/package working as expected (so that you see the expected images and placeholders) then build out the APK and distribute via Firebase App Distribution and any Android device.

### Configuration

**Version:**
cached_network_image: ^2.2.0+1
Android Studio 4.1
classpath 'com.android.tools.build:gradle:4.1.0'

**Platform:**
- Android (on Samsung and HTC phones)