Bump cloud_controller_ng

Changes in cloud_controller_ng:

- Dev: Add periodic Gem freshness report
    PR: cloudfoundry/cloud_controller_ng#4782
    Author: Johannes Haass <[email protected]>

Dependency updates in cloud_controller_ng:

- build(deps): bump middleman-syntax from 3.4.0 to 3.6.1 in /docs/v3
    PR: cloudfoundry/cloud_controller_ng#4590
    Author: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: ari-wg-gitbot