Please upgrade OPA engine to v1 in order to support Rego v1 syntax in Harness policies.

Release: https://github.com/open-policy-agent/opa/releases/tag/v1.0.0

Announcement: https://blog.openpolicyagent.org/announcing-opa-1-0-a-new-standard-for-policy-as-code-a6d8427ee828

Doc: https://www.openpolicyagent.org/docs/v0-upgrade