Bump gh-pages from 1.1.0 to 2.1.1 (#295)

Bumps [gh-pages](https://github.com/tschaub/gh-pages) from 1.1.0 to 2.1.1.
- [Release notes](https://github.com/tschaub/gh-pages/releases)
- [Changelog](https://github.com/tschaub/gh-pages/blob/master/changelog.md)
- [Commits](tschaub/gh-pages@v1.1.0...v2.1.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -37,7 +37,7 @@
     "eslint-plugin-import": "^2.17.2",
     "eslint-plugin-jsx-a11y": "^5.1.1",
     "eslint-plugin-react": "^7.13.0",
-    "gh-pages": "^1.1.0",
+    "gh-pages": "^2.1.1",
     "lerna": "^3.14.1",
     "style-loader": "^0.23.1",
     "uglify-es": "^3.2.1",