General Akka.TestKit fixes that are found while porting tests to async#5773

Aaronontheweb merged 1 commit intoakkadotnet:feature/async_testkitakkadotnet/akka.net:feature/async_testkitfrom

Arkatufus:async_testkit/general_fixArkatufus/akka.net:async_testkit/general_fixCopy head branch name to clipboard