Jennifer Maas TV Business Writer Coming off a lot of Emmys love, ABC comedy “Abbott Elementary” went back in session Wednesday with a Season 2 premiere that kept pace with its freshman finale last spring. According to Nielsen’s Live + Same Day data, Episode 1 of Season 2 averaged a 0.5 rating among adults ages 18-49 and 2.8 million total viewers, tying it with “The Conners” Season premiere for ABC’s highest-rated show during Wednesday primetime. That marks a solid start to the new school year for “Abbott Elementary,” which put up a 0.6 rating and 2.8 million total viewers in the comparable Nielsen metrics for its Season 1 finale in April.