The output of the method you mentioned is not the one we need in ValidateStorageAccount() for ConnectionQualifiers. You can find the output of  CloudServiceClient.GetStorageServiceConnectionString  below.
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DefaultEndpointsProtocol=https;AccountName=myaccoount;AccountKey=m1CAzBXaY/AkaW0Rz+XteXolhTeai9juTePsMkIG+eJ0T4FsO4R