Fixed typos in MongoDB Atlas Vector Search documentation (#7174)

Fix for typos in MongoDB Atlas Vector Search documentation
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docs/extras/modules/data_connection/vectorstores/integrations/mongodb_atlas.ipynb

@@ -1,6 +1,7 @@
 {
  "cells": [
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "683953b3",
    "metadata": {},
@@ -44,6 +45,7 @@
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "457ace44-1d95-4001-9dd5-78811ab208ad",
    "metadata": {},
@@ -63,6 +65,7 @@
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "1f3ecc42",
    "metadata": {},
@@ -130,7 +133,7 @@
     "# initialize MongoDB python client\n",
     "client = MongoClient(MONGODB_ATLAS_CLUSTER_URI)\n",
     "\n",
-    "db_name = \"lanchain_db\"\n",
+    "db_name = \"langchain_db\"\n",
     "collection_name = \"langchain_col\"\n",
     "collection = client[db_name][collection_name]\n",
     "index_name = \"langchain_demo\"\n",
@@ -156,6 +159,7 @@
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "851a2ec9-9390-49a4-8412-3e132c9f789d",
    "metadata": {},
@@ -183,14 +187,14 @@
     "db_name = \"langchain_db\"\n",
     "collection_name = \"langchain_col\"\n",
     "collection = client[db_name][collection_name]\n",
-    "index_name = \"langchain_index\"\n",
+    "index_name = \"langchain_demo\"\n",
     "\n",
     "# initialize vector store\n",
     "vectorStore = MongoDBAtlasVectorSearch(\n",
     "    collection, OpenAIEmbeddings(), index_name=index_name\n",
     ")\n",
     "\n",
-    "# perform a similarity search between the embedding of the query and the embeddings of the documents\n",
+    "# perform a similarity search between a query and the ingested documents\n",
     "query = \"What did the president say about Ketanji Brown Jackson\"\n",
     "docs = vectorStore.similarity_search(query)\n",
     "\n",