Fixed bug for NormalizationTransformer on singletask datasets
Fixed bug for NormalizationTransformer on singletask datasets

Agent007/deepchem,miaecle/deepchem,lilleswing/deepchem,ktaneishi/deepchem,joegomes/deepchem,Agent007/deepchem,rbharath/deepchem,Agent007/deepchem,miaecle/deepchem,deepchem/deepchem,miaecle/deepchem,peastman/deepchem,lilleswing/deepchem,deepchem/deepchem,ktaneishi/deepchem,joegomes/deepchem,lilleswing/deepchem,ktaneishi/deepchem,rbharath/deepchem,peastman/deepchem