Bump next from 7.0.0 to 7.0.2 in /frontend

Bumps [next](https://github.com/zeit/next.js) from 7.0.0 to 7.0.2.
- [Release notes](https://github.com/zeit/next.js/releases)
- [Commits](vercel/next.js@7.0.0...7.0.2)

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

Author: dependabot[bot]