how to avoid tokenizing w/ sklearn feature extraction
You can change the tokenizer instead of the token pattern. The token pattern is used by the tokenizer. You can set as tokenizer any function that returns a list of string. For example, str.split

tokenizer=str.split


From the official documentation,


  tokenizer callable, default=None
  
  Override the string tokenization step while preserving the preprocessing and n-grams generation steps. Only applies if analyzer == 'word'.