Brian Steinberg Senior TV Editor “Saturday Night Live” is trying to replenish its ranks after many of its best-known cast members have signaled they intend to leave the show. The venerable NBC late-night program has enlisted four new featured players for its 48th season, a move that will lend some ballast to the cast after mainstays like Kate McKinnon and Aidy Bryant decided to leave. In many years, “”Saturday Night Live”” taps two or three new players per season, so four is more than the show typically brings on board. The four new featured players include Marcello Hernandez, Molly Kearney, Michael Longfellow and Devon Walker. Hernandez, who bills himself as a writer, comedian and producer, is a Cuban-Dominican stand-up who has opened for Tim Dillon, Jim Breuer, Mark Viera, Gilbert Gottfried and others. Kearney is a Chicago-based comic. Longfellow, who hails from Arizona, has done stand up in Los Angeles. And Walker, who has made a few lists of up-and-coming comedians recently, hails from New York City.