chore: multi-node testkit throttle not implemented in Artery

[patriknw]

This has always been the case but showed up after removing classic remoting #31765
I'm surprised but that means that the TestConductorSpec was previously only running with classic.

multi-node test failure:

2022-11-30T02:52:42.0237412Z �[0m[�[0m�[0minfo�[0m] �[0m�[0m[�[34mJVM-2�[0m] scala.MatchError: SetThrottle(akka://TestConductorSpec@test-node1:5000,Send,TokenBucket(1000,1249.9999720603228,0,0)) (of class akka.remote.testkit.SetThrottle)�[0m
2022-11-30T02:52:42.0239423Z �[0m[�[0m�[0minfo�[0m] �[0m�[0m[�[34mJVM-2�[0m] 	at akka.remote.artery.ArteryTransport.managementCommand(ArteryTransport.scala:673)�[0m

[johanandren]

LGTM