Fix appservice sky typo

Author: craigshoemaker

articles/storage/blobs/storage-upload-process-images.md

@@ -100,7 +100,7 @@ Create an App Service plan with the [az appservice plan create](/cli/azure/appse
 The following example creates an App Service plan named `myAppServicePlan` in the **Free** pricing tier:
 
 ```azurecli-interactive
-az appservice plan create --name myAppServicePlan --resource-group myResourceGroup --sku FREE
+az appservice plan create --name myAppServicePlan --resource-group myResourceGroup --sku Free
 ```
 
 ## Create a web app