[Android] Deletes deprecated splash screen meta-data element (#130744)

Deletes deprecated splash screen meta-data element.

This is no longer needed to present a splash screen in a Flutter application, but will be removed soon. See [go/flutter-splash-screen-migration](http://go/flutter-splash-screen-migration) for more information.

Part of https://github.com/flutter/flutter/issues/105173.

dev/integration_tests/deferred_components_test/android/app/src/main/AndroidManifest.xml

@@ -28,15 +28,6 @@ found in the LICENSE file. -->
               android:name="io.flutter.embedding.android.NormalTheme"
               android:resource="@style/NormalTheme"
               />
-            <!-- Displays an Android View that continues showing the launch screen
-                 Drawable until Flutter paints its first frame, then this splash
-                 screen fades out. A splash screen is useful to avoid any visual
-                 gap between the end of Android's launch screen and the painting of
-                 Flutter's first frame. -->
-            <meta-data
-              android:name="io.flutter.embedding.android.SplashScreenDrawable"
-              android:resource="@drawable/launch_background"
-              />
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>

packages/flutter_tools/test/integration.shard/test_data/deferred_components_project.dart

@@ -508,15 +508,6 @@ class BasicDeferredComponentsConfig extends DeferredComponentsConfig {
                 android:name="io.flutter.embedding.android.NormalTheme"
                 android:resource="@style/NormalTheme"
                 />
-              <!-- Displays an Android View that continues showing the launch screen
-                   Drawable until Flutter paints its first frame, then this splash
-                   screen fades out. A splash screen is useful to avoid any visual
-                   gap between the end of Android's launch screen and the painting of
-                   Flutter's first frame. -->
-              <meta-data
-                android:name="io.flutter.embedding.android.SplashScreenDrawable"
-                android:resource="@drawable/launch_background"
-                />
               <intent-filter>
                   <action android:name="android.intent.action.MAIN"/>
                   <category android:name="android.intent.category.LAUNCHER"/>