Truncate max length if needed in all examples
# What does this PR do?

As pointed out in #10015, most examples will let the tokenzation and training run when `tokenizer.model_max_length < max_seq_length` and the default value is sometimes bigger than the max length for some models (like BertTweet). This PR addresses that.

Fixes #10015
@sgugger Thanks for fixing this. I made this mistake again (running many jobs at once with different models) and my jobs didn't crash (meanwhile I had upgraded to the latest transformers 🚀  )