Update structured_outputs.ipynb (#2666)

docs/backend/structured_outputs.ipynb

@@ -4,14 +4,13 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "# Constrained Decoding"
+    "# Structured Outputs (JSON, Regex, EBNF)"
    ]
   },
   {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Structured Outputs (JSON, Regex, EBNF)\n",
     "You can specify a JSON schema, [regular expression](https://en.wikipedia.org/wiki/Regular_expression) or [EBNF](https://en.wikipedia.org/wiki/Extended_Backus%E2%80%93Naur_form) to constrain the model output. The model output will be guaranteed to follow the given constraints. Only one constraint parameter (`json_schema`, `regex`, or `ebnf`) can be specified for a request.\n",
     "\n",
     "SGLang supports two grammar backends:\n",