Fixed typo on max_gpu_mem

ColorizeTrainingStable.ipynb

@@ -96,7 +96,7 @@
     "# Enable PyTorch LMS\n",
     "torch.cuda.set.enabled_lms(True)\n",
     "# Set LMS limit\n",
-    "torch.cuda.set_limit_lms(gb_to_bytes(max_gpu_memory))"
+    "torch.cuda.set_limit_lms(gb_to_bytes(max_gpu_mem))"
    ]
   },
   {