* Use 'onErrorContinue' to continue receiving messages from Stream
* Send an `ErrorMessage` to the provided `errorChannel` (if any)
* And `@Nullable` to some `MessageProducerSupport` API which definitely
may accept `null`
* Extract common `buildMessageFromRecord()` method in the `ReactiveRedisStreamMessageProducer`,
so all the headers from the stream `Record` are carried to the message independently of the
record state - normal send or error sending
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