[Speech2Text] Slow tests are failing on master
Currently the following tests are failing on master:

```
FAILED tests/test_modeling_speech_to_text.py::Speech2TextModelIntegrationTests::test_generation_librispeech
FAILED tests/test_modeling_speech_to_text.py::Speech2TextModelIntegrationTests::test_generation_librispeech_batched
```
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