Bump react/datagram from 1.8.0 to 1.9.0

Bumps [react/datagram](https://github.com/reactphp/datagram) from 1.8.0 to 1.9.0.
- [Release notes](https://github.com/reactphp/datagram/releases)
- [Changelog](https://github.com/reactphp/datagram/blob/1.x/CHANGELOG.md)
- [Commits](reactphp/datagram@v1.8.0...v1.9.0)

---
updated-dependencies:
- dependency-name: react/datagram
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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