Bugs

• #5320 : Using WebSocketClient with jetty-websocket-httpclient.xml in a Jetty web application causes ClassCastException
• #5521 : ResourceCollection NPE in list()
• #5555 : NPE for servlet with no mapping

Enhancements

• #5488 : jetty-dir.css not found when using JPMS
• #5498 : ServletHolder lifecycle correctness
• #5535 : Support regex in SslContextFactory include/exclude of protocols