Revert "MULE-6988:  The jetty transport does not have an option to configure the number of acceptor threads"

This reverts commit 86415a4c7b041dcadb123c0db2f97d6e10577894.
Revert "EE-3372: Refactoring so that logic is reusable"

This reverts commit 469f6767de768f3913ece45e1c6fa1d9edbdb343.