build(deps): bump send and express in /docker/async-slowapp

Bumps [send](https://github.com/pillarjs/send) to 1.2.0 and updates ancestor dependency [express](https://github.com/expressjs/express). These dependencies need to be updated together.


Updates `send` from 0.17.1 to 1.2.0
- [Release notes](https://github.com/pillarjs/send/releases)
- [Changelog](https://github.com/pillarjs/send/blob/master/HISTORY.md)
- [Commits](pillarjs/send@0.17.1...1.2.0)

Updates `express` from 5.0.0-alpha.8 to 5.1.0
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@5.0.0-alpha.8...v5.1.0)

---
updated-dependencies:
- dependency-name: send
  dependency-version: 1.2.0
  dependency-type: indirect
- dependency-name: express
  dependency-version: 5.1.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]