By Michael Tedder Dwayne “The Rock” Johnson has the look, but critics are mixed on the new Warner Bros. Discovery film ‘Black Adam.” So if you have no idea who Black Adam is, or why there’s a movie about him, there’s a long answer and a short answer. The longer answer, which we covered here, is that Warner Bros. Discovery (WBD) – Get Warner Bros. Discovery Inc. Report has a lot invested in the universe of films based around characters from DC Comics. But in the nearly ten years this universe has existed, the results have been uneven at best, with some high points (“Wonder Woman”) and some misf…