Failed to use KeyphraseCountVectorizer with Keybert 0.7.0

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KeyphraseCountVectorizer used to work with Keybert but now with 0.7.0 it failed with highlight_document():

```
def highlight_document(
doc: str, keywords: List[Tuple[str, float]], vectorizer: CountVectorizer
):
keywords_only = [keyword for keyword, _ in keywords]
max_len = vectorizer.ngram_range[1]
```

Exception says:
```
AttributeError: 'KeyphraseCountVectorizer' object has no attribute 'ngram_range'
```
which is expected for KeyphraseCountVectorizer.

Please kindly advise, thanks.

Start at highlight_document() in the issue and reproduce the AttributeError with KeyphraseCountVectorizer on KeyBERT 0.7.0. Trace how the function reads vectorizer.ngram_range, then verify the behavior with both CountVectorizer and KeyphraseCountVectorizer; done means highlighting no longer fails for the latter.

Written by the indexing model from the issue text.