protected function setUpSiteConfigFile($sitePath, $relativeThemePath, $themeName)
    {
        $source = $sitePath.'/'.$relativeThemePath.'/config.yml';
        $destination = $sitePath.'/config.yml';

        $this->fs->copy($source, $destination, true);

        $configContent = file_get_contents($destination);
        $configValues = Yaml::parse($configContent);
        $configValues['themes'] = ['name' => $themeName];

        $configParsed = Yaml::dump($configValues);

        $this->fs->dumpFile($destination, $configParsed);
    }