Deprecate instrumentation for Jetty 9, 10, 11 that is out of support

[shakuzen]

Community support has already ended for Jetty versions 9, 10, 11 - see jetty/jetty.project#10485. I don't know that it makes sense for us to maintain multiple copies of instrumentation for versions of a library that is no longer in community support. We recently added Jetty 12 instrumentation for server and client side (#4324 #4261). With that, I think we can deprecate any Jetty instrumentation we have that doesn't work with Jetty 12 and refer users in the deprecation notice to the Jetty 12 instrumentation.