Fixed typo missing "use" (#5991)

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Fixed a simple typo on
https://python.langchain.com/en/latest/modules/indexes/retrievers/examples/vectorstore.html
where the word "use" was missing.

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docs/modules/indexes/retrievers/examples/vectorstore.ipynb

@@ -99,13 +99,14 @@
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "2d958271",
    "metadata": {},
    "source": [
     "## Similarity Score Threshold Retrieval\n",
     "\n",
-    "You can also a retrieval method that sets a similarity score threshold and only returns documents with a score above that threshold"
+    "You can also use a retrieval method that sets a similarity score threshold and only returns documents with a score above that threshold"
    ]
   },
   {