Update ItagItem.java

Author: kapodamy

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/ItagItem.java

@@ -39,9 +39,9 @@ public class ItagItem {
             new ItagItem(139, AUDIO, M4A, 48),
             new ItagItem(140, AUDIO, M4A, 128),
             new ItagItem(141, AUDIO, M4A, 256),
-            new ItagItem(249, AUDIO, OPUS, 50),
-            new ItagItem(250, AUDIO, OPUS, 70),
-            new ItagItem(251, AUDIO, OPUS, 160),
+            new ItagItem(249, AUDIO, WEBMA_OPUS, 50),
+            new ItagItem(250, AUDIO, WEBMA_OPUS, 70),
+            new ItagItem(251, AUDIO, WEBMA_OPUS, 160),
 
             /// VIDEO ONLY ////////////////////////////////////////////
             //           ID      Type     Format  Resolution  FPS  ///