RBAC: REST proxy needs client configs for Docker cub util kafka-ready

[ybyzek]

• In Docker environments (using CP REST Proxy images), https://github.com/confluentinc/cp-demo/blob/5.5.0-post/docker-compose.yml#L905-L913 is required for kafka-ready command which is used in https://github.com/confluentinc/kafka-rest-images/blob/master/kafka-rest/include/etc/confluent/docker/ensure#L29-L33

• In non-Docker environments, https://github.com/confluentinc/cp-demo/blob/5.5.0-post/docker-compose.yml#L905-L913 is NOT required

  • Hence https://github.com/confluentinc/examples/blob/5.5.0-post/security/rbac/delta_configs/kafka-rest.properties.delta does not have these client.* configs