Update MediaBrowser.Controller/Lyrics/LyricResponse.cs

Co-authored-by: Niels van Velzen <nielsvanvelzen@users.noreply.github.com>

MediaBrowser.Controller/Lyrics/LyricResponse.cs

@@ -10,7 +10,7 @@ public class LyricResponse
     /// <summary>
     /// Gets or sets Metadata.
     /// </summary>
-    public LyricMetadata? Metadata { get; set; }
+    public LyricMetadata Metadata { get; set; }
 
     /// <summary>
     /// Gets or sets Lyrics.