Knative 0.23.x has dropped the beta/alpha versions of some objects:
https://github.com/knative/eventing/releases/tag/v0.23.3 (See Breaking session)

Thus, new installations of Knative do not support integration with our Operator. Mainly, SinkBinding won't work anymore. We need to upgrade and handle the old objects accordingly. As soon as we get KogitoSource on sandbox, we will remove this dependency. But up until there, would be nice to have it working.