If the first season of “Russian Doll” was protagonist Nadia Vulvokov’s own personal “Groundhog Day,” the second season is “Back to the Future.” More than three years after Harry Nilsson’s track “Gotta Get Up” was permanently seared into your brain as it played repeatedly during the first season, the Netflix dark comedy returns Wednesday for its second. This time, instead of outrunning death, Nadia is outrunning her own history. “In season one, it’s about how do I stop dying. In season two, it’s a question of how do I stop living,” Natasha Lyonne, who stars as Nadia and has taken over as showru…