docs: fix vectara description at https://python.langchain.com/docs/integrations/tools/ All tools section (#31427)

…tegrations/tools/ All tools section

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docs/docs/integrations/tools/vectara.ipynb

@@ -7,8 +7,6 @@
    "source": [
     "# Vectara\n",
     "\n",
-    "## Overview\n",
-    "\n",
     "[Vectara](https://vectara.com/) is the trusted AI Assistant and Agent platform which focuses on enterprise readiness for mission-critical applications. For more [details](../providers/vectara.ipynb).\n",
     "\n",
     "\n",