LOS ANGELES (AP) — Tamara Lawrance is a busy young British actor. In the first few years of her career, she played a fictional girlfriend to Prince Harry in the 2017 TV movie “King Charles III,” and was in an episode of filmmaker Steve McQueen’s 2020 “Small Axe” anthology. Glowing reviews met each performance, as they have for the three-part miniseries called “The Long Song,” airing Sunday on PBS. The drama is set in the final days of slavery in 19th-century Jamaica and stars Lawrance as July, from her early years working in a plantation owner’s house to liberated later life.