Adding new key field to .env example

.env.example

@@ -1,7 +1,8 @@
 OPENAI_API_KEY=your_api_key
 LANGSMITH_API_KEY=your_langsmith_api_key #Find it here: https://smith.langchain.com
 PORT=3000
+NARAKEET_API_KEY=your_narakeet_api_key
 #FLASK_ENV=development #Optional if you want docker to reload flask when you save your code.
 #LANGSMITH_API_KEY=your_api_key #optional. Let's you debug using langsmith
 #LANGCHAIN_PROJECT=your_project_name #pops up in langsmith dashboard
-#TAVILY_API_KEY=your_api_key #Needed for the AI to search the web. The tool will be disabled if there's no api key
+#TAVILY_API_KEY=your_api_key #Needed for the AI to search the web. The tool will be disabled if there's no api key