Fix comment typo

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162368534

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaAdsLoader.java

@@ -123,7 +123,7 @@ public final class ImaAdsLoader implements ExoPlayer.EventListener, VideoAdPlaye
    */
   private int adGroupIndex;
   /**
-   * Whether IMA has send an ad event to pause content since the last resume content event.
+   * Whether IMA has sent an ad event to pause content since the last resume content event.
    */
   private boolean imaPausedContent;
   /**