Updated XQuartz URL

dlib/CMakeLists.txt

@@ -283,7 +283,7 @@ if (NOT TARGET dlib)
                message(" *****************************************************************************")
                message(" *** DLIB GUI SUPPORT DISABLED BECAUSE X11 DEVELOPMENT LIBRARIES NOT FOUND ***")
                message(" *** Make sure XQuartz is installed if you want GUI support.               ***")
-               message(" *** You can download XQuartz from: http://xquartz.macosforge.org/landing/ ***")
+               message(" *** You can download XQuartz from: https://www.xquartz.org/               ***")
                message(" *****************************************************************************")
                set(DLIB_NO_GUI_SUPPORT ON CACHE STRING ${DLIB_NO_GUI_SUPPORT_STR} FORCE )
                enable_preprocessor_switch(DLIB_NO_GUI_SUPPORT)