Improve experience with TOKENIZERS_PARALLELISM

[n1t0]

The message is not explicit enough, so some users don't understand that they should set an environment variable. Also, we could probably provide a function that, given a boolean, would set it for the user.

[cornzz]

Hi, I am using the zeroscrolls metric to evaluate something and I am getting this message, I have no idea if I should set this variable to true or false since I didnt write the code using the tokenizer and also dont know where this is coming from because the message doesnt tell that. What do I do?

[ArthurZucker]

You can probably ignore it, or do something like export TOKENIZER_PARALLELISM=1