Brian Steinberg Senior TV EditorCNN’s coming foray into the streaming wars will send the network searching for customers in both regular haunts and surprising places.The WarnerMedia cable-news outlet typically runs a significant chunk of promotions for its programming on its own air and in other venues owned by its parent company. On Friday, it’s airing an initial ad to entice loyal viewers to consider CNN Plus, its new video-streaming service slated to launch in 2022.