Fix DTensor concepts link

Author: james47

site/en/tutorials/distribute/dtensor_ml_tutorial.ipynb

@@ -70,7 +70,7 @@
       "source": [
         "## Overview\n",
         "\n",
-        "DTensor provides a way for you to distribute the training of your model across devices to improve efficiency, reliability and scalability. For more details, check out the [DTensor concepts](../guide/dtensor_overview.ipynb) guide.\n",
+        "DTensor provides a way for you to distribute the training of your model across devices to improve efficiency, reliability and scalability. For more details, check out the [DTensor concepts](../../guide/dtensor_overview.ipynb) guide.\n",
         "\n",
         "In this tutorial, you will train a sentiment analysis model using DTensors. The example demonstrates three distributed training schemes:\n",
         "\n",