Preheat the oven to 325 degrees F (165 degrees C). Spray a 9x5-inch loaf pan with cooking spray. Mash bananas in a large bowl with a fork. Add brown sugar, molasses, oil, eggs, and 1/4 cup milk. Stir until combined. Stir flour, ginger, cinnamon, baking soda, cloves, allspice, and salt together in another bowl. Stir flour mixture into the banana mixture until just incorporated. Pour into the prepared pan. Bake in the preheated oven until a toothpick inserted into the center comes out clean, 60 to 70 minutes. Let cool completely, at least 30 minutes. Turn bread out of the pan. Combine 1 tablespoon milk, corn syrup, and butter in a bowl. Add confectioners' sugar and stir. Add vanilla extract and enough remaining milk to achieve a drizzling consistency. Pour glaze over the cooled bread.