Add missing libNetx to linking

CMakeLists.txt

@@ -4,7 +4,7 @@ list(APPEND CMAKE_PREFIX_PATH ${ROOTSYS})
 set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake/modules")
 find_package(JSONC REQUIRED)
 find_package(libwebsockets REQUIRED)
-find_package(ROOT REQUIRED COMPONENTS Net Tree)
+find_package(ROOT REQUIRED COMPONENTS Net Netx Tree)
 foreach(FEATURE xrootd xml)
   if(NOT ROOT_${FEATURE}_FOUND)
     message(FATAL_ERROR "ROOT was built without ${FEATURE} support (required)")