Remove unused import

src/main/java/com/kdanmobile/reader/copyfile/CopyFileViewModel.kt

@@ -7,7 +7,6 @@ import android.content.Context
 import android.content.Intent
 import com.kdanmobile.reader.event.EventBroadcaster
 import com.kdanmobile.reader.event.EventManager
-import com.kdanmobile.reader.thumb.FileUtil
 import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.disposables.Disposable
 import io.reactivex.schedulers.Schedulers