public TextToSpeechProviderFactory(
IYamlFileReader <AmazonPolly.Settings> amazonPollySettingsFileReader = null,
IYamlFileReader <Google.Settings> googleSettingsFileReader = null)
{
_amazonPollySettingsFileReader = amazonPollySettingsFileReader ?? new YamlFileReader <AmazonPolly.Settings>();
_googleSettingsFileReader = googleSettingsFileReader ?? new YamlFileReader <Google.Settings>();
}