Function mz_storage_client::sink::publish_kafka_schemas

async fn publish_kafka_schemas(
    ccsr: &Client,
    topic: &str,
    key_schema: Option<&str>,
    key_schema_type: Option<SchemaType>,
    value_schema: &str,
    value_schema_type: SchemaType
) -> Result<(Option<i32>, i32), Error>

Publish value and optional key schemas for a given topic.

TODO(benesch): do we need to delete the Kafka topic if publishing the schema fails?