Lankyboy’s “Summerland,” not to be confused with the 2020 Gemma Arterton-starring period piece of the same name, is a contemporary coming-of-age movie set on the road to a mythical music festival. The film stars Maddie Phillips (“Teenage Bounty Hunters”) as Stacey, Rory J. Saper (Hulu’s “Find Me in Paris”) as Oliver, and Chris Ball (Art...