Heat olive oil in a skillet over medium heat. Cook and stir onion in the hot oil until softened, 5 to 10 minutes. Add chickpeas and garlic to onion; cook and stir until heated through, about 5 minutes. Mix red pepper flakes, lemon juice, salt, and pepper into chickpea mixture; cook and stir for 3 minutes more. Stir parsley and mint into salad.