fix: ObjectDisposedException on Unity Transport shutdown [backport]#3152

NoelStephensUnity merged 4 commits intodevelopUnity-Technologies/com.unity.netcode.gameobjects:developfrom

fix/exception_on_transport_shutdown_backportUnity-Technologies/com.unity.netcode.gameobjects:fix/exception_on_transport_shutdown_backportCopy head branch name to clipboard