Fix BM25Tokenizer to correctly handle tokenization language

[elampe-freeday]

Problem

The word_tokenize function has a language parameter, which defaults to 'english'. However, when this function is called within the BM25Tokenizer, the language parameter is not passed, so it always defaults to 'english', even if self.language is set to a different value.

Solution

Added self.language to the arguments of word_tokenize in the BM25Tokenizer class.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Infrastructure change (CI configs, etc)
• Non-code change (docs, etc)
• None of the above: (explain here)

Test Plan

Describe specific steps for validating this change.

[mjvankampen]

@acatav is this repo still maintained? Is there an alternative you would recommend switching to?