[ERROR] Found files or folders in non-standard locations in the project! [ERROR] ....This might be a side-effect of a migration to Android Maven Plugin 4+.
android-maven-plugin-4.0 uses the new Android Studio folder layout which is much more Mavenish.
- Android resources should be is src\main\res,
- Android assets in src\main\assets,
- AndroidManifest.xml in src\main