Don't call begin_training if updating new model (see #3059) [ci skip]
Don't call begin_training if updating new model (see #3059) [ci skip]

explosion/spaCy,spacy-io/spaCy,honnibal/spaCy,spacy-io/spaCy,spacy-io/spaCy,honnibal/spaCy,spacy-io/spaCy,honnibal/spaCy,explosion/spaCy,spacy-io/spaCy,honnibal/spaCy,explosion/spaCy,explosion/spaCy,explosion/spaCy,explosion/spaCy,spacy-io/spaCy