fix bug of CLAP dataloader 
Author: lukewys
Pull request: yes

Fix the bug of the CLAP data loader (https://github.com/LAION-AI/CLAP/issues/62)

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Fixes # (issue)


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Comments:
_The documentation is not available anymore as the PR was closed or merged._

cc @younesbelkada and @ArthurZucker 

Just an FYI that the slow tests aren't actually being run for CLAP. See also https://github.com/huggingface/transformers/pull/22834