docs: fix pdfloaders' descriptions at https://python.langchain.com/docs/integrations/document_loaders/ All document loaders section (#31371)

…cs/integrations/document_loaders/ All document loaders section

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docs/docs/integrations/document_loaders/unstructured_pdfloader.ipynb

@@ -6,8 +6,6 @@
       "source": [
         "# UnstructuredPDFLoader\n",
         "\n",
-        "## Overview\n",
-        "\n",
         "[Unstructured](https://unstructured-io.github.io/unstructured/) supports a common interface for working with unstructured or semi-structured file formats, such as Markdown or PDF. LangChain's [UnstructuredPDFLoader](https://python.langchain.com/api_reference/community/document_loaders/langchain_community.document_loaders.pdf.UnstructuredPDFLoader.html) integrates with Unstructured to parse PDF documents into LangChain [Document](https://python.langchain.com/api_reference/core/documents/langchain_core.documents.base.Document.html) objects.\n",
         "\n",
         "Please see [this page](/docs/integrations/providers/unstructured/) for more information on installing system requirements.\n",
@@ -34,7 +32,9 @@
     {
       "cell_type": "markdown",
       "metadata": {},
-      "source": "To enable automated tracing of your model calls, set your [LangSmith](https://docs.smith.langchain.com/) API key:"
+      "source": [
+        "To enable automated tracing of your model calls, set your [LangSmith](https://docs.smith.langchain.com/) API key:"
+      ]
     },
     {
       "cell_type": "code",

docs/docs/integrations/document_loaders/zeroxpdfloader.ipynb

@@ -6,7 +6,6 @@
    "source": [
     "# ZeroxPDFLoader\n",
     "\n",
-    "## Overview\n",
     "`ZeroxPDFLoader` is a document loader that leverages the [Zerox](https://github.com/getomni-ai/zerox) library. Zerox converts PDF documents into images, processes them using a vision-capable language model, and generates a structured Markdown representation. This loader allows for asynchronous operations and provides page-level document extraction.\n",
     "\n",
     "### Integration details\n",