Unable to execute run_simple() with different models of the same type

[TimDettmers]

Describe the bug

When one uses run_simple() with different models of the same type roberta-base and roberta-large the run crashes because the code assumes they are the same model because weights are saved under hf_config.model_type (instead of args.hf_pretrained_model_name_or_path.). As such, the code tries to load incompatible weights and crashes.

To Reproduce

1. Install jiant
2. Run the simple example in README
3. Change the model in the sample from 'roberta-basetoroberta-large`

Expected behavior
One should be able to run run_simple() with different models of the same type.

Screenshots
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Additional context
Solution: The hf_config.model_type should be used for caching tokenizer / tasks. The args.hf_pretrained_model_name_or_path for the weights.