R.I.P CNN+. Warner Bros. Discovery is shutting it down April 30, a month after its highly touted launch which included CNN+ getting Chris Wallace from Fox News. Was it a concept that was killed to soon or a concept that should never have gone from concept to reality?Warner Bros. Discovery is shutting down CNN+ as of April 30, marking one of the company’s first significant maneuvers since completing the merger of WarnerMedia and Discovery less than two weeks ago. The decision puts an abrupt end to an ambitious and aggressive venture that people familiar with the matter say rankled David Zaslav,…