“Ozark” fans, rejoice. The Jason Bateman and Julia Garner-starring drama series is returning to Netflix in April with a second part to its fourth season — and it’s just one of many other hotly anticipated titles coming to the streamer this month. April will also see the long-awaited sophomore installment to “Russian Doll,” the mind-bending “Groundhog Day”-esque dramedy series starring Natasha Lyonne as a hard-partying New York City woman stuck in a brain-melting circuitous loop from hell. For fans of capital-M mess, there’s the Spanish-language “Elite,” which traces the scandalous (and often murderous) exploits of the posh attendees of high school Las Encinas.