Bump express from 4.16.2 to 4.16.4

Bumps [express](https://github.com/expressjs/express) from 4.16.2 to 4.16.4.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@4.16.2...4.16.4)

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

Author: dependabot-support