Respect documentation on passive log level (#21700)

* Respect documentation on passive log level

* Fix test and set log level in examples

* Add doc

examples/pytorch/audio-classification/run_audio_classification.py

@@ -209,6 +209,10 @@ def main():
         handlers=[logging.StreamHandler(sys.stdout)],
     )
 
+    if training_args.should_log:
+        # The default of training_args.log_level is passive, so we set log level at info here to have that default.
+        transformers.utils.logging.set_verbosity_info()
+
     log_level = training_args.get_process_log_level()
     logger.setLevel(log_level)
     transformers.utils.logging.set_verbosity(log_level)