bugfix: fix minor bugs

utils/completion_reward.py

@@ -425,10 +425,10 @@ class MTKAgent:
                 ).json()
                 response_text = response["choices"][0]["message"]["content"]
 
-                matched_content = re.search("```(.+)", response_text, re.DOTALL)
-                extracted_content = (
-                    matched_content.group(1).strip() if matched_content else None
-                )
+                matched_contents = re.findall("```(.*?)```", response_text, re.DOTALL)
+
+                # Concatenate all extracted contents
+                extracted_content = "\n".join(matched_contents).strip()
 
                 chinese_converter = OpenCC("s2tw")