Fixes#7265
I took a look at the new Observation API, and I think that it still
makes sense to continue using the interceptors to implement this
instrumentation: they implement the OTel spec (which includes way more
attributes than the default observation convention implemented in
Spring), and cooperate with the Kafka client instrumentation and link
the receive and process spans together. And it's quite a simple change
in one of our interceptors, instead of rewriting everything.
(Draft because Spring Boot 3 hasn't released yet, and it is required to
run the tests. If we're not in a hurry this PR can wait a bit for that)
Lauri Tulmin
Mateusz Rzeszutek
Trask Stalnaker