added clarifying comments

Author: solbell2

Basic_Samples/Chat/chatGPT_managing_conversation.ipynb

@@ -53,6 +53,7 @@
     "deployment_name = os.environ['CHAT_COMPLETIONS_MODEL']\n",
     "\n",
     "# The base URL for your Azure OpenAI resource. e.g. \"https://<your resource name>.openai.azure.com\"\n",
+    "# This is the value of the endpoint for your Azure OpenAI resource\n",
     "azure_endpoint = os.environ['AZURE_OPENAI_ENDPOINT']\n",
     "\n",
     "# The API key for your Azure OpenAI resource.\n",