Build Jekyll
@param done
@param errorShouldExit {Boolean} [false] - Should it stop the script if an error happens?
@param watchTask {Boolean} [false] - Is this a watch task?
function build(done, errorShouldExit, watchTask) {
    const cd = config.cwd ? `cd ${config.cwd} && ` : '';
    core.utils.sh(`${cd}${config.commandPrefix} build --incremental${watchTask ? ' --watch' : ''}`, errorShouldExit, (err) => {
      done(err);
    });
  }