Sheet Pan Chicken Shawarma

Name: Sheet Pan Chicken Shawarma
Ingredients: 2 tablespoons olive oil; 1 teaspoon ground cumin; 1/2 teaspoon ground cinnamon; 1/4 teaspoon ground allspice; 1/4 teaspoon ground cardamom; 1/4 teaspoon ground turmeric; 2 cloves garlic, grated; Kosher salt and freshly ground black pepper; 1 pound boneless, skinless chicken thighs, sliced into 1-inch-thick pieces; 1 medium onion (about 6 ounces), halved and sliced into 1-inch-thick half-moons; 1/2 cup full-fat Greek yogurt; Juice of 1/2 lemon; 4 pieces pita bread; 3 dill pickle spears, chopped; 1 Roma tomato (about 6 ounces), chopped; 1 cup shredded lettuce