feat(per-app-language): add Android config plugin

[jetaix]

Why

This plugin simplifies the process of implementing per-app language preferences in your React Native Android app.

It allows users to set a specific language for your app, independent of their system-wide language settings.

How

This plugin automates the manual setup process described in the Android documentation for implementing per-app language preferences

Test Plan

To ensure that the @config-plugins/react-native-android-per-app-language plugin is working correctly, follow these steps:

• After running expo prebuild, check that the AndroidManifest.xml file in your Android project contains the android:localeConfig="@xml/locales_config" attribute in the <application> tag.
• Verify that a locales_config.xml file has been created in the android/app/src/main/res/xml/ directory.
• Ensure that the locales_config.xml file contains all the languages specified in your supportedLanguages configuration.