Sanity check the type of id2label and label2id arguments of from_pretrained for TokenClassification models
Fixes #20773 

Sanity check the type of id2label and label2id arguments of from_pretrained for TokenClassification models
_The documentation is not available anymore as the PR was closed or merged._<|||||>@sgugger One of TF test is failing due to timeout. Not sure if it is related to changes . 
<|||||>No, this isn't linked to the PR. Thanks for your contribution!