Add `library_name: transformers` metadata tag

This PR improves the model card by adding the `library_name: transformers` metadata tag. This addition is based on the `config.json` and `tokenizer_config.json` files, which indicate the model's compatibility with the Hugging Face Transformers library (e.g., `GPT2LMHeadModel`, `GPT2Tokenizer`, `transformers_version`).

Adding this tag will enable the automated "How to use" widget on the model page, providing users with a convenient and predefined code snippet for loading and utilizing the model with the 🤗 Transformers library.

README.md

@@ -1,15 +1,17 @@
 ---
-license: apache-2.0
+base_model:
+- openai-community/gpt2
 datasets:
 - databricks/databricks-dolly-15k
 language:
 - en
+license: apache-2.0
 metrics:
 - rouge
-base_model:
-- openai-community/gpt2
 pipeline_tag: text-generation
+library_name: transformers
 ---
+
 # init-gpt2-120M
 
 [paper](https://arxiv.org/abs/2306.08543) | [code](https://github.com/microsoft/LMOps/tree/main/minillm)