Preheat the oven to 350°F. Coat a nonstick mini-muffin tin with natural butter-flavored cooking spray and press a wonton square into each cup of the tin, forming a wonton cup. Lightly coat the wonton cups with cooking spray and bake for 12 minutes or until golden brown. Let cool in the pan. Meanwhile, in a medium bowl, stir together the chicken, yogurt, mayonnaise, chutney, curry powder, and salt. Then add the celery, grapes, and cilantro and stir. With a spoon, stuff about 2 tablespoons of the salad into each wonton cup. Garnish each with a tiny sprig of cilantro or a red grape sliver, if desired.