docs: fix model2vec description at https://python.langchain.com/docs/integrations/text_embedding/ All embedding models section (#31349)

…integrations/document_loaders/ All document loaders section

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docs/docs/integrations/text_embedding/model2vec.ipynb

@@ -5,8 +5,6 @@
    "id": "e8712110",
    "metadata": {},
    "source": [
-    "## Overview\n",
-    "\n",
     "Model2Vec is a technique to turn any sentence transformer into a really small static model\n",
     "[model2vec](https://github.com/MinishLab/model2vec) can be used to generate embeddings."
    ]