community: Rename deployments server to AI gateway (#26368)

We recently renamed `MLflow Deployments Server` to `MLflow AI Gateway`
in mlflow. This PR updates the relevant notebooks to use `MLflow AI
gateway`

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---------

Signed-off-by: harupy <17039389+harupy@users.noreply.github.com>
Co-authored-by: Erick Friis <erick@langchain.dev>

docs/vercel.json

@@ -73,6 +73,10 @@
     {
       "source": "/v0.2/docs/templates/:path(.*/?)*",
       "destination": "https://github.com/langchain-ai/langchain/tree/master/templates/:path*"
+    },
+    {
+      "source": "/docs/integrations/providers/mlflow_ai_gateway(/?)",
+      "destination": "/docs/integrations/providers/mlflow/"
     }
   ]
 }