Update README.md with license information

Hi, I'm Chen, a DevRel specialist from 01.AI.
We have updated our license from yi-license to apache-2.0, and this PR is about the update for your model.
Apache-2.0 enables more free and flexible use and distribution, promoting open collaboration and innovation.
If it looks good to you, you can update other Yi model derivatives now licensed under yi-license to apache-2.0.
Thanks for your understanding and cooperation.

README.md

@@ -1,9 +1,6 @@
 ---
-license: other
 tags:
 - merge
-license_name: yi-license
-license_link: https://huggingface.co/01-ai/Yi-34B-200K/blob/main/LICENSE
 model-index:
 - name: 2xbagel-dpo-34b-v0.2
   results:
@@ -107,6 +104,7 @@ model-index:
     source:
       url: https://huggingface.co/spaces/HuggingFaceH4/open_llm_leaderboard?query=TeeZee/2xbagel-dpo-34b-v0.2
       name: Open LLM Leaderboard
+license: apache-2.0
 ---
 # Bagel DPO 57B