=per #15459 Use full batching for persistAsync and defer

(cherry picked from commit 20ac844b4f3999d0261f1a08957c2c2a8367c672)

Conflicts:
	akka-bench-jmh/src/main/scala/akka/persistence/PersistenceActorDeferBenchmark.scala
Merge pull request #15463 from akka/wip-15459-persistAsync-batching-master-patriknw

=per #15459 Use full batching for persistAsync and defer (for validation)