Changelog

• #13646 - Improve HTTP/2 and HTTP/3 invalid header value exception message
• #13637 - 12.0.x: H2 reset: fix missing callback completion
• #13618 - Jetty 12.1.x simplified epc no pending (#13372)
• #13603 - Bad Accept-Language request headers can result in NPE during HttpServletRequest.getLocale() call
• #13598 - Server hangs when client closes too many connections.
• #13586 - Merge back Release/12.0.27
• #13583 - NPE in WriteFlusher after org.eclipse.jetty.http.BadMessageException: 417
• #13509 - "No multipart configuration element" exception when getNamedDispatcher().forward() used