Upgrade IMA SDK dependency to 3.22.3

This brings in a fix for `NullPointerExceptions` within `WebView` callbacks in
the IMA SDK.

Issue: #8447
PiperOrigin-RevId: 363627446

RELEASENOTES.md

@@ -68,9 +68,14 @@
     *   Fix `onPositionDiscontinuity` event so that it is not triggered with
         reason `DISCONTINUITY_REASON_PERIOD_TRANSITION` after a seek to another
         media item and so that it is not triggered after a timeline change.
-*   IMA extension: fix error caused by `AdPlaybackState` ad group times being
-    cleared, which can occur if the `ImaAdsLoader` is released while an ad is
-    pending loading ([#8693](https://github.com/google/ExoPlayer/issues/8693)).
+*   IMA extension:
+    *   Fix error caused by `AdPlaybackState` ad group times being cleared,
+        which can occur if the `ImaAdsLoader` is released while an ad is
+        pending loading
+        ([#8693](https://github.com/google/ExoPlayer/issues/8693)).
+    *   Upgrade IMA SDK dependency to 3.22.3, fixing an issue with
+        `NullPointerExceptions` within `WebView` callbacks
+        ([#8447](https://github.com/google/ExoPlayer/issues/8447)).
 
 ### 2.13.2 (2021-02-25)
 

extensions/ima/build.gradle

@@ -25,7 +25,7 @@ android {
 }
 
 dependencies {
-    api 'com.google.ads.interactivemedia.v3:interactivemedia:3.22.0'
+    api 'com.google.ads.interactivemedia.v3:interactivemedia:3.22.3'
     implementation project(modulePrefix + 'library-core')
     implementation 'androidx.annotation:annotation:' + androidxAnnotationVersion
     implementation 'com.google.android.gms:play-services-ads-identifier:17.0.0'