[TAPAS] Tiny fix
# What does this PR do?

This PR includes a finy fix for TAPAS. Namely, when `config.select_one_column` is set to `False`, the model should not recompute the token logits. 

Relevant to #13393
Can you include a test to ensure the behavior doesn't happen in the future?<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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