Uninstalls the default configuration of a given extension.
string $type: The extension type; e.g., 'module' or 'theme'.
string $name: The name of the module or theme to install default configuration for.
function config_uninstall_default_config($type, $name) {
$storage = drupal_container()
->get('config.storage');
$config_names = $storage
->listAll($name . '.');
foreach ($config_names as $config_name) {
config($config_name)
->delete();
}
}