Update oj requirement from ~> 2.18 to >= 2.18, < 4.0
Update oj requirement from ~> 2.18 to >= 2.18, < 4.0

Updates the requirements on [oj](https://github.com/ohler55/oj) to permit the latest version.
- [Release notes](https://github.com/ohler55/oj/releases)
- [Changelog](https://github.com/ohler55/oj/blob/develop/CHANGELOG.md)
- [Commits](https://github.com/ohler55/oj/compare/v2.18.0...v3.10.1)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
sensu-plugins/sensu-plugins-http