[examples] replicate the new `--log_level` feature to all trainer-based pytorch examples

https://github.com/huggingface/transformers/pull/12276 introduced a new --log_level feature, which now allows users to set their desired log level via CLI or TrainingArguments.

run_translation.py was used as a “model” for other examples.

Now we need to replicate this to all other Trainer-based examples under examples/pytorch/, the 3 changes are

1. importing datasets
2. using training_args.get_node_log_level() and setting log_level in 3 modules
3. replacing datasets object name with raw_datasets, since otherwise we have a conflict with datasets the module.

and the relevant diff is here

and of course since we don’t quite have extensive tests for examples, you can just test with a staple cmd from the corresponding README.md with --log_level=error and check that almost all logs are gone.

This is open to all.

And thank you.

[stas00]

@bhadreshpsavani, once https://github.com/huggingface/transformers/pull/12309 gets merged, please rebase your branch and rename

-    get_node_log_level()
+    get_process_log_level()

Thank you!

[stas00]

Yes, of course! Thank you, @bhadreshpsavani