Update README: rename Code Repository to Source Code

README.md

@@ -40,7 +40,7 @@ default_config_name: UltraData-Math-L3-Conversation-Synthetic
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 <p align="center">
-<a href="https://huggingface.co/datasets/openbmb/UltraData-Math">🤗 Dataset</a> | <a href="https://github.com/UltraData-OpenBMB/UltraData-Math">💻 Code Repository</a> | <a href="README_ZH.md">🇨🇳 中文 README</a>
+<a href="https://huggingface.co/datasets/openbmb/UltraData-Math">🤗 Dataset</a> | <a href="https://github.com/UltraData-OpenBMB/UltraData-Math">💻 Source Code</a> | <a href="README_ZH.md">🇨🇳 中文 README</a>
 </p>
 
 ## 📚 Introduction