Place crushed biscuits into a bowl and pour melted butter over them; mix until combined and the crust mixture holds together. Combine mascarpone cheese, pumpkin puree, sweetened condensed milk, sugar, cinnamon, nutmeg, and cloves in a large bowl. Beat using an electric mixer until filling is smooth and airy. Line 24 cups of a mini-muffin pan with paper liners. Press 1 teaspoon of crust mixture into the bottom of each cup. Spoon 1 teaspoon filling over each crust and smooth the top. Place a pecan on top of each. Chill cheesecakes in the refrigerator for 2 hours.