Kafka channel dispatcher logs HTTP error 502 on malformed response from an event handling client function

[ntzlqx]

Describe the bug
The issue does not result in a real failure if the response is not meaningful, but creates confusion in logs and traces.
There is an explicit conversion in code of a http status code 200 to 502 without some additional logging context

Expected behavior
Clear indication that the client function responded with a malformed cloudevent

To Reproduce
Respond from a kn handler function with 200 and something else (non empty response body) such as string or anything other than cloud event

0.17.3

Additional context
Add any other context about the problem here such as proposed priority

[ntzlqx]

/approve

[ntzlqx]

Thank you guys!