`:wrap-jetty-handler` option no longer has any effect since 0.30/Jetty 12

[svdm]

I've found the :wrap-jetty-handler to be very handy for wrapping the app handler created by the adapter in one or more Jetty handlers. However, in the current release the option is never used, though it is still listed and destructured in run-jetty. This seems to have happened in the changes required for Jetty 12, ie. 0.30.0.

Is it feasible to restore this functionality or is there a better way to do this in Jetty 12?