chore(deps): Bump express and parse-dashboard

Bumps [express](https://github.com/expressjs/express) to 4.21.0 and updates ancestor dependency [parse-dashboard](https://github.com/ParsePlatform/parse-dashboard). These dependencies need to be updated together.


Updates `express` from 4.18.1 to 4.21.0
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/4.21.0/History.md)
- [Commits](expressjs/express@4.18.1...4.21.0)

Updates `parse-dashboard` from 5.4.0 to 6.0.0
- [Release notes](https://github.com/ParsePlatform/parse-dashboard/releases)
- [Changelog](https://github.com/parse-community/parse-dashboard/blob/alpha/CHANGELOG.md)
- [Commits](parse-community/parse-dashboard@5.4.0...6.0.0)

---
updated-dependencies:
- dependency-name: express
  dependency-type: indirect
- dependency-name: parse-dashboard
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>