Cook ground beef and onions in a skillet over medium heat until beef is browned, 7 to 10 minutes; drain grease. Stir in water and taco seasoning; cook, stirring often, until thickened, about 2 minutes. Add refried beans, salsa, olives, and green chiles. Cook and stir over low heat until ingredients are warmed through, 3 to 4 minutes.