Reactive Jetty, Tomcat, and Undertow management servers do not apply management_ prefix to their access logs

[wilkinsona]

A web app using the servlet stack with a separate management server will write the management server's access logs to a file prefixed with management_. When you switch to WebFlux using Jetty, Tomcat, or Undertow, the main and management servers use the same location for their access logs. The reactive side of things needs a fix that was similar to #6618, which was made before we had reactive web support.

While the two servers writing access logs to the same location is a bug, there's a small chance that it's a load-bearing bug. Given that no users have reported the problem, I'm going to fix this only in 3.5.x. We can back port the changes in the future if necessary.