feat(videoplayer): add closed captions (#4036)

### Related Ticket(s)

#4012 

### Description

Add closed caption button to `VideoPlayer`.

### Changelog

**New**

- closed captioning button to Kaltura video player

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<!-- *** "package: services": Services -->
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packages/services/src/services/VideoPlayer/VideoPlayer.js

@@ -192,6 +192,9 @@ class VideoPlayerAPI {
           entry_id: videoId,
           flashvars: {
             autoPlay: autoPlay,
+            closedCaptions: {
+              plugin: true,
+            },
             titleLabel: {
               plugin: true,
               align: 'left',