Remove GeneratedPluginRegistrant.java (#42981)

dev/integration_tests/android_embedding_v2_smoke_test/android/app/src/main/java/dev/flutter/plugins/GeneratedPluginRegistrant.java

-package dev.flutter.plugins;
-
-import androidx.annotation.NonNull;
-import io.flutter.embedding.engine.FlutterEngine;
-import io.flutter.embedding.engine.plugins.shim.ShimPluginRegistry;
-
-/**
- * Generated file. Do not edit.
- * This file is generated by the Flutter tool based on the
- * plugins that support the Android platform.
- */
-public final class GeneratedPluginRegistrant {
-  public static void registerWith(@NonNull FlutterEngine flutterEngine) {
-    ShimPluginRegistry shimPluginRegistry = new ShimPluginRegistry(flutterEngine);
-    io.flutter.plugins.battery.BatteryPlugin.registerWith(shimPluginRegistry.registrarFor("io.flutter.plugins.battery.BatteryPlugin"));
-  }
-}