community: add missing link (#23526)

libs/community/langchain_community/utilities/tavily_search.py

@@ -1,6 +1,7 @@
 """Util that calls Tavily Search API.
 
 In order to set this up, follow instructions at:
+https://docs.tavily.com/docs/tavily-api/introduction
 """
 import json
 from typing import Dict, List, Optional

libs/community/langchain_community/utilities/you.py

@@ -1,6 +1,7 @@
 """Util that calls you.com Search API.
 
 In order to set this up, follow instructions at:
+https://documentation.you.com/quickstart
 """
 
 import warnings