Update lemmaitzer docs [ci skip]
@@ -35,8 +35,8 @@ Lemmatize a string.
>
> ```python
> from spacy.lemmatizer import Lemmatizer
-> from spacy.lang.en import LEMMA_INDEX, LEMMA_EXC, LEMMA_RULES
-> lemmatizer = Lemmatizer(LEMMA_INDEX, LEMMA_EXC, LEMMA_RULES)
+> rules = {"noun": [["s", ""]]}
+> lemmatizer = Lemmatizer(index={}, exceptions={}, rules=rules)
> lemmas = lemmatizer("ducks", "NOUN")
> assert lemmas == ["duck"]
> ```
