Add ACCESS_NETWORK_STATE permission for MH tests

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=218058185

playbacktests/src/androidTest/AndroidManifest.xml

@@ -18,6 +18,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     package="com.google.android.exoplayer2.playbacktests">
 
+  <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
   <uses-permission android:name="android.permission.INTERNET"/>
   <uses-permission android:name="android.permission.WAKE_LOCK"/>