“ Jean-Michel ” is the Jean-Michel Basquiat documentary we’ve been waiting for — the fantastic one he deserves. Over the years, there have been a sprinkling of films built around Basquiat, like the boho vérité snapshot “Downtown 81” (2000) or “ Boom for Real: The Late Teenage Years of Jean-Michel Basquiat” (2018), which captured the period in the late ’70s after he’d broken with his family, when he was a scene-maker cultivating the seeds of his art and fame. Both those films are heady time