DOCS: Fix typo in MongoDB memory docs (#13588)

- **Description:** Fix typo in MongoDB memory docs
  - **Tag maintainer:** @eyurtsev

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  - **Description:** Fix typo in MongoDB memory docs
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docs/docs/integrations/memory/mongodb_chat_message_history.ipynb

@@ -5,7 +5,7 @@
    "id": "91c6a7ef",
    "metadata": {},
    "source": [
-    "# MongodDB\n",
+    "# MongoDB\n",
     "\n",
     ">`MongoDB` is a source-available cross-platform document-oriented database program. Classified as a NoSQL database program, `MongoDB` uses `JSON`-like documents with optional schemas.\n",
     ">\n",