Cucumber and Avocado Salad

24 sprigs cilantro 1/4 cup coarsely chopped cilantro leaves 1/4 cup chopped peeled ginger 6 garlic cloves, lightly crushed 2 dried chiles de ├írbol 2 English hothouse cucumbers (about 2 pounds total), cut into 1/2″ pieces 1 teaspoon (or more) kosher salt 1...