minor style fix

source/examples/xgboost-rf-gpu-cpu-benchmark/notebook.ipynb

@@ -25,7 +25,7 @@
     "\n",
     "In the notebook demo below, we compare benchmarking results to show how GPU can accelerate HPO tuning jobs relative to CPU.\n",
     "\n",
-    "For instance, we find a 48x speedup in wall clock time (0.71 hrs vs 34.6 hrs) for XGBoost and 16x (3.86 hrs vs 63.2 hrs) for RandomForest when comparing between `p3.8xlarge` Tesla V100 GPUs  and `c5.24xlarge` CPU EC2 instances on 100 HPO trials on 3 years of the Airline Dataset.\n",
+    "For instance, we find a 48x speedup in wall clock time (0.71 hrs vs 34.6 hrs) for XGBoost and 16x (3.86 hrs vs 63.2 hrs) for RandomForest when comparing between `p3.8xlarge` Tesla V100 GPUs  and `c5.24xlarge` CPU EC2 instances on 100 HPO trials of the 3-year Airline Dataset.\n",
     "\n"
    ]
   },