[Shoebox] Allow storage to be ommited when disabling diagnostic settings.

Author: vcanaa

src/ResourceManager/Insights/Commands.Insights/Diagnostics/SetAzureRmDiagnosticSettingCommand.cs

@@ -42,7 +42,8 @@ public class SetAzureRmDiagnosticSettingCommand : ManagementCmdletBase
         /// <summary>
         /// Gets or sets the storage account parameter of the cmdlet
         /// </summary>
-        [Parameter(Mandatory = true, ValueFromPipelineByPropertyName = true, HelpMessage = "The storage account id")]
+        [Parameter(Mandatory = false, ValueFromPipelineByPropertyName = true, HelpMessage = "The storage account id")]
+        [ValidateNotNullOrEmpty]
         public string StorageAccountId { get; set; }
 
         /// <summary>