readRedirectsFile = async (redirectsPath) => {
    try {
        return await fs.readFile(redirectsPath, 'utf-8');
    } catch (err) {
        if (err.code === 'ENOENT') {
            return '';
        }

        if (errors.utils.isGhostError(err)) {
            throw err;
        }

        throw new errors.NotFoundError({
            err: err
        });
    }
}
@param {string} redirectsPath
@returns {Promise<string>}