He put on 30 pounds of muscle to ensure that he’d keep the role of Jacob Black in the “Twilight” films, but Taylor Lautner insists he’s sick of feeling like a musclehead. The 17-year-old heartthrob revealed that he can’t wait for the vampire film franchise to be over so that he can go back to being a bit smaller and quit the daily intense workouts. An insider told press, “Normally Taylor is m…