Bump next from 8.1.0 to 9.0.0 (#145)

Bumps [next](https://github.com/zeit/next.js) from 8.1.0 to 9.0.0.
- [Release notes](https://github.com/zeit/next.js/releases)
- [Commits](vercel/next.js@v8.1.0...v9.0.0)

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

package.json

@@ -26,7 +26,7 @@
     "evergreen-ui": "^4.17.0",
     "firebase": "^6.2.4",
     "imagemin-optipng": "^7.0.0",
-    "next": "^8.1.0",
+    "next": "^9.0.0",
     "next-auth": "^1.12.1",
     "next-compose-plugins": "^2.2.0",
     "next-optimized-images": "^2.5.3",