Update rasa_nlu/featurizers/ngram_featurizer.py
Update rasa_nlu/featurizers/ngram_featurizer.py

Co-Authored-By: tmbo <96835dd8bfa718bd6447ccc87af89ae1675daeca@rasa.com>
RasaHQ/rasa_nlu,RasaHQ/rasa_nlu,RasaHQ/rasa_nlu