Andrew Black

@tim-finnigan - I'm not certain `xargs` would be of much assistance, as it wouldn't help with the structuring of the output of multiple invocations of the aws cli into something...

With the modification to `directory_data_source_test.go`, I've rerun the test, producing the following output ```console % make testacc TESTS=TestAccWorkSpacesDataSource_serial/Directory PKG=workspaces make: Verifying source code with gofmt... ==> Checking that code complies...