Fix typo in 'understanding-billing.md'

Author: JillGrant615

articles/storage/files/understanding-billing.md

@@ -143,7 +143,7 @@ Currently, these SKUs are generally available in a limited subset of regions:
 - Poland Central
 - West US 3
 
-Storage accounts in regions flagged with an asterisks (*) can only be created using Azure PowerShell or Azure CLI. See [create a storage account](./storage-how-to-create-file-share.md) for more information.
+Storage accounts in regions flagged with an asterisk (*) can only be created using Azure PowerShell or Azure CLI. See [create a storage account](./storage-how-to-create-file-share.md) for more information.
 
 ### Provisioned v2 provisioning detail
 When you create a provisioned v2 file share, you specify the provisioned capacity for the file share in terms of storage, IOPS, and throughput. File shares are limited based on the following attributes: