Fix a 404 link in send_request.ipynb (#5280)

Signed-off-by: windsonsea <haifeng.yao@daocloud.io>

docs/backend/send_request.ipynb

@@ -166,7 +166,7 @@
    "source": [
     "## Using Native Generation APIs\n",
     "\n",
-    "You can also use the native `/generate` endpoint with requests, which provides more flexiblity. An API reference is available at [Sampling Parameters](../references/sampling_params.md)."
+    "You can also use the native `/generate` endpoint with requests, which provides more flexiblity. An API reference is available at [Sampling Parameters](sampling_params.md)."
    ]
   },
   {