readFixtureBrowsers(name) {
    const filePath = this.fixturePath(name, ".browsers");
    const exists = fs.existsSync(filePath);
    return (
      exists &&
      fs
        .readFileSync(filePath, "utf8")
        .split("\n")[0]
        .trim()
    );
  }
read a fixture browsers
@param {String} name
@return the fixture browsers string