Worker attribute description of http-listener and https-listener is incorrect

Description of worker for attribute of http-listener and https-listener is incorrect as it states "The AJP listeners XNIO worker", which is correct only for ajp listener and not for http and https listener.

This impacts both description in model and also description copied to documentation to Configuration guide appendix describing undertow attributes.

As this impacts also documentation anrobert_jira might be interested in this one as well.