Brian Steinberg Senior TV Editor What do Valentine’s Day and the ubiquitous zombies of AMC’s “The Walking Dead” have in common (other than a potential focus on the human heart)? More than you might think. The creatures and the protagonists who try to stop them get an unlikely shout out Wednesday when AMC launches a new promo to tout “The Walking Dead: The Ones Who Live,” the third in a series of character-driven spin-offs that have launched since the end of the original series in 2022.