fix lint @OptIn lint error

Signed-off-by: parneet-guraya <gurayaparneet@gmail.com>

app/src/main/java/com/nextcloud/client/media/NextcloudExoPlayer.kt

@@ -22,6 +22,7 @@
 package com.nextcloud.client.media
 
 import android.content.Context
+import androidx.annotation.OptIn
 import androidx.media3.common.util.UnstableApi
 import androidx.media3.datasource.DefaultDataSource
 import androidx.media3.datasource.okhttp.OkHttpDataSource
@@ -38,7 +39,7 @@ object NextcloudExoPlayer {
      * IP versions and certificates.
      *
      */
-    @UnstableApi
+    @OptIn(UnstableApi::class)
     @JvmStatic
     fun createNextcloudExoplayer(context: Context, nextcloudClient: NextcloudClient): ExoPlayer {
         val okHttpDataSourceFactory = OkHttpDataSource.Factory(nextcloudClient.client)

app/src/main/java/com/owncloud/android/ui/preview/PreviewMediaFragment.java

@@ -82,6 +82,7 @@ import java.util.concurrent.Executors;
 import javax.inject.Inject;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.OptIn;
 import androidx.annotation.StringRes;
 import androidx.appcompat.app.ActionBar;
 import androidx.appcompat.app.AppCompatActivity;
@@ -96,7 +97,7 @@ import androidx.media3.common.MediaItem;
 import androidx.media3.common.util.UnstableApi;
 import androidx.media3.exoplayer.ExoPlayer;
 
-@UnstableApi
+@OptIn(markerClass = UnstableApi.class)
 /**
  * This fragment shows a preview of a downloaded media file (audio or video).
  * <p>