Remove CompositionPlayer activity from the transformer demo app

The CompositionPlayer is not ready yet.

Issue: androidx#741
PiperOrigin-RevId: 574859927

Author: droid-girl

demos/transformer/src/main/AndroidManifest.xml

@@ -64,11 +64,5 @@
         android:label="@string/app_name"
         android:exported="true"
         android:theme="@style/Theme.MaterialComponents.DayNight.NoActionBar"/>
-    <activity android:name=".CompositionPreviewActivity"
-      android:configChanges="keyboard|keyboardHidden|orientation|screenSize|screenLayout|smallestScreenSize|uiMode"
-      android:launchMode="singleTop"
-      android:label="@string/app_name"
-      android:exported="true"
-      android:theme="@style/Theme.MaterialComponents.DayNight.NoActionBar"/>
   </application>
 </manifest>