Add Description about Default MLAssist Compute Cluster

if we couldn't create cluster due to insufficient quota, we don't know which quota is lack. so we need to add description about default MLAssist compute cluster vm size.

Author: KazuOnuki

articles/machine-learning/how-to-create-image-labeling-projects.md

@@ -168,7 +168,7 @@ To accelerate labeling tasks, on the **ML assisted labeling** page, you can trig
 
 At the start of your labeling project, the items are shuffled into a random order to reduce potential bias. However, the trained model reflects any biases that are present in the dataset. For example, if 80 percent of your items are of a single class, then approximately 80 percent of the data used to train the model lands in that class.
 
-To enable assisted labeling, select **Enable ML assisted labeling** and specify a GPU. If you don't have a GPU in your workspace, a GPU cluster is created for you and added to your workspace. The cluster is created with a minimum of zero nodes, which means it costs nothing when not in use.
+To enable assisted labeling, select **Enable ML assisted labeling** and specify a GPU. If you don't have a GPU in your workspace, a GPU cluster (resource name: DefLabelNC6v3, vmsize: Standard_NC6s_v3) is created for you and added to your workspace. The cluster is created with a minimum of zero nodes, which means it costs nothing when not in use.
 
 ML-assisted labeling consists of two phases: