Update vesearch.py

Author: yaozheng-fang

veadk/tools/builtin_tools/vesearch.py

@@ -30,7 +30,7 @@ def vesearch(query: str) -> str:
     bot_id = str(getenv("TOOL_VESEARCH_ENDPOINT"))
 
     if api_key == "":
-        return "Invoke `vesearch` failed. Please set VESEARCH_API_KEY as your environment variable."
+        return "Invoke `vesearch` failed. Please set TOOL_VESEARCH_API_KEY as your environment variable."
     if bot_id == "":
         return "Invoke `vesearch` failed. Please set VESEARCH_BOT_ID as your environment variable."