Update /en/lessons/analyzing-multilingual-text-nltk-spacy-stanza

[anisa-hawes]

I am preparing some updates to the EN lesson analyzing-multilingual-text-nltk-spacy-stanza.

In the process of translation into French, and in response to recent feedback from a reader, Émilien Schultz has prepared a sequence of updates to the lesson + the accompanying Python notebook, and has re-tested the lesson.

Closes #3713

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