Deliver message properties to the sink

[MaxShvets]

Problem
I have a RabbitMQ source configured to send events to a knative service. When I send a message to the queue, an event arrives to my service, but it doesn't have any of the properties (such as "headers" or "reply-to"). In particular, this makes it impossible for me to respond to the message, but even if responding can be handled some other way, I'd still like to be able to receive the headers.

Persona:
Event consumer

Exit Criteria
All properties of the message are added to the cloud event delivered to the source's sink

Time Estimate (optional):
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Additional context (optional)
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