Pork Gyro Burgers With Marinated Cucumbers

Name: Pork Gyro Burgers With Marinated Cucumbers
Ingredients: 3 Persian cucumbers, sliced ¼ inch thick; ¼ teaspoon crushed red pepper; 4 garlic cloves, finely chopped, divided; 1 teaspoon kosher salt, divided; 1 cup parsley leaves; 1½ pounds ground pork; 2 teaspoons dried oregano; 1 teaspoon dried thyme; ¾ teaspoon black pepper; 2 tablespoons extra-virgin olive oil; 4 pitas, warmed; Greek yogurt and sliced red onion, for serving