Update README.md

The dolly-v2-3b model is truly impressive in its instruction-following capabilities. We would love to contribute by updating the README to include accurate information about the base model. This effort aims to enhance the completeness of the model card. Thank you !

README.md

@@ -7,6 +7,8 @@ inference: false
 datasets:
 - databricks/databricks-dolly-15k
 duplicated_from: databricks/dolly-v2-3b
+base_model:
+- EleutherAI/pythia-2.8b
 ---
 # dolly-v2-3b Model Card
 ## Summary