chore(package): update serve-static to version 1.12.3
chore(package): update serve-static to version 1.12.3

https://greenkeeper.io/
ExactTarget/fuelux,cormacmccarthy/fuelux,futuremint/fuelux,ExactTarget/fuelux,cormacmccarthy/fuelux,futuremint/fuelux