Bump test-kitchen from 2.11.2 to 2.12.0 in /omnibus
Bump test-kitchen from 2.11.2 to 2.12.0 in /omnibus

Bumps [test-kitchen](https://github.com/test-kitchen/test-kitchen) from 2.11.2 to 2.12.0.
- [Release notes](https://github.com/test-kitchen/test-kitchen/releases)
- [Changelog](https://github.com/test-kitchen/test-kitchen/blob/master/CHANGELOG.md)
- [Commits](https://github.com/test-kitchen/test-kitchen/compare/v2.11.2...v2.12.0)

---
updated-dependencies:
- dependency-name: test-kitchen
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
chef/chef-server,chef/chef-server,chef/chef-server,chef/chef-server,chef/chef-server,chef/chef-server