Woody Harrelson thought his work was clogged up with more serious roles leading into “White House Plumbers.” The “Champions” actor compared the HBO true crime limited series to the cabler’s mystery-thriller anthology show “True Detective,” in which he and Matthew McConaughey starred as a pair of grizzled homicide detectives. Despite only appearing in the first season, both actors serve as executive producers on the series, which returns with a fourth season later this year. “White House Plumbers” writer Peter Huyck now recalls Harrelson being hesitant to sign on to the series coming off “True Detective.” “When we all went up to your house to try and convince you to do the part, you said, ‘Look, I did “True Detective” and McConaughey got the cool part, the fun part.