Remove versions from IMA demo manifest that are now specified via gradle
Remove versions from IMA demo manifest that are now specified via gradle

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=189000217

google/ExoPlayer,tntcrowd/ExoPlayer,amzn/exoplayer-amazon-port,stari4ek/ExoPlayer,ebr11/ExoPlayer,superbderrick/ExoPlayer,superbderrick/ExoPlayer,google/ExoPlayer,MaTriXy/ExoPlayer,stari4ek/ExoPlayer,amzn/exoplayer-amazon-port,saki4510t/ExoPlayer,ened/ExoPlayer,androidx/media,saki4510t/ExoPlayer,superbderrick/ExoPlayer,ened/ExoPlayer,ebr11/ExoPlayer,ened/ExoPlayer,androidx/media,saki4510t/ExoPlayer,MaTriXy/ExoPlayer,tntcrowd/ExoPlayer,stari4ek/ExoPlayer,MaTriXy/ExoPlayer,androidx/media,google/ExoPlayer,amzn/exoplayer-amazon-port,tntcrowd/ExoPlayer,ebr11/ExoPlayer