Update README.md

The DeciLM-7B-instruct model is truly impressive! We would love to contribute by updating the README to include the base_model information. This will help address the missing details in the model card.

README.md

@@ -4,6 +4,8 @@ language:
 - en
 datasets:
 - Open-Orca/SlimOrca
+base_model:
+- Deci/DeciLM-7B
 ---
 # DeciLM-7B-instruct