fix: tokenizer when no tokens

[julesbertrand]

Description

When no tokens are retrieved for a text (e.g. preprocessing removed all words), then tokenizer is returning a ValueError about spacy lan_model not supported

• the check for spacy lan_model should be done beforehand
• if text is empty, tokens can be empty and should be returned as an empty list

+ Bump dependencies to latest available using poetry lock

Related Issue

Type of Change

• 📚 Examples / docs / tutorials / dependencies update
• 🔧 Bug fix (non-breaking change which fixes an issue)
• 🥂 Improvement (non-breaking change which improves an existing feature)
• 🚀 New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 🔐 Security fix

Checklist

• I've read the CODE_OF_CONDUCT.md document.
• I've read the CONTRIBUTING.md guide.
• I've updated the code style using make format-code.
• I've written tests for all new methods and classes that I created.
• I've written the docstring in Google format for all the methods and classes that I used.