adding support for commonsense qa for multiple choice question answering
Can somebody help me in fixing the failed test?<|||||>Hi, thanks for your addition, that's really cool! Did you check the [contributions guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md#start-contributing-pull-requests)?

You should make sure you have the correct versions of `black`, `isort` and `flake8` installed and then run `make style`/`make quality` to identify the code quality issues.<|||||>This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.
