Fixed doc - aks snapshot show to aks nodepool snapshot

Changed "az aks snapshot show" to "az aks nodepool snapshot show"

Author: SreejaBhattacharya-MSFT

articles/aks/node-pool-snapshot.md

@@ -49,7 +49,7 @@ az aks snapshot create --name MySnapshot --resource-group MyResourceGroup --node
 First you'll need the resource ID from the snapshot that was previously created, which you can get from the command below:
 
 ```azurecli-interactive
-SNAPSHOT_ID=$(az aks snapshot show --name MySnapshot --resource-group myResourceGroup --query id -o tsv)
+SNAPSHOT_ID=$(az aks nodepool snapshot show --name MySnapshot --resource-group myResourceGroup --query id -o tsv)
 ```
 
 Now, we can use the command below to add a new node pool based off of this snapshot.
@@ -65,7 +65,7 @@ You can upgrade a node pool to a snapshot configuration so long as the snapshot
 First you'll need the resource ID from the snapshot that was previously created, which you can get from the command below:
 
 ```azurecli-interactive
-SNAPSHOT_ID=$(az aks snapshot show --name MySnapshot --resource-group myResourceGroup --query id -o tsv)
+SNAPSHOT_ID=$(az aks nodepool snapshot show --name MySnapshot --resource-group myResourceGroup --query id -o tsv)
 ```
 
 Now, we can use this command to upgrade this node pool to this snapshot configuration.
@@ -84,7 +84,7 @@ When you create a cluster from a snapshot, the cluster original system pool will
 First you'll need the resource ID from the snapshot that was previously created, which you can get from the command below:
 
 ```azurecli-interactive
-SNAPSHOT_ID=$(az aks snapshot show --name MySnapshot --resource-group myResourceGroup --query id -o tsv)
+SNAPSHOT_ID=$(az aks nodepool snapshot show --name MySnapshot --resource-group myResourceGroup --query id -o tsv)
 ```
 
 Now, we can use this command to create this cluster off of the snapshot configuration.