function deployToGhPages(repo) {
  return (done) => {
    const d = new Date();
    const m = `Deploying ${d.getMonth() + 1}-${d.getDate()}-${d.getFullYear()}`;
    ghpages.publish(
      'gh-pages',
      {
        message: m,
        repo,
        // Include .nojekyll file to tell GitHub to publish without building.
        // By default, dotfiles are excluded.
        // TODO: make the github action include .nojekyll.
        src: ['**/*', '.nojekyll'],
      },
      done,
    );
  };
}
Deploy all plugins to gh-pages.
@param {string=} repo The repo to deploy to.
@returns {Function} Gulp task.