Update crossbeam-channel requirement from 0.3.9 to 0.4.0
Update crossbeam-channel requirement from 0.3.9 to 0.4.0

Updates the requirements on [crossbeam-channel](https://github.com/crossbeam-rs/crossbeam) to permit the latest version.
- [Release notes](https://github.com/crossbeam-rs/crossbeam/releases)
- [Changelog](https://github.com/crossbeam-rs/crossbeam/blob/master/CHANGELOG.md)
- [Commits](https://github.com/crossbeam-rs/crossbeam/compare/crossbeam-channel-0.3.9...crossbeam-channel-0.4.0)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
spacejam/sled,spacejam/sled,spacejam/sled