Update notebook link (#19)

Author: rbs333

python-recipes/RAG/02_langchain.ipynb

@@ -12,7 +12,7 @@
         "This notebook uses [LangChain](https://python.langchain.com/docs/get_started/introduction) and [Redis](https://redis.com) to perform document + embdding indexing and semantic search tasks. It also shows how to integrate with an LLM like OpenAI's GPT models.\n",
         "\n",
         "## Let's Begin!\n",
-        "<a href=\"https://colab.research.google.com/github/redis-developer/redis-ai-resources/blob/main/python-recipes/RAG/03_langchain.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
+        "<a href=\"https://colab.research.google.com/github/redis-developer/redis-ai-resources/blob/main/python-recipes/RAG/02_langchain.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
       ]
     },
     {