Ladybird/WebDriver: Support running headless WebDriver sessions

This adds a dependency from WebDriver to Lagom's headless-browser to be
used if the client's required capabilities indicate to do so.

Ladybird/WebDriver/main.cpp

@@ -6,6 +6,7 @@
 
 #define AK_DONT_REPLACE_STD
 
+#include "../Utilities.h"
 #include <LibCore/ArgsParser.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/System.h>
@@ -36,6 +37,8 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
         return 1;
     }
 
+    platform_init();
+
     Core::EventLoop loop;
     auto server = TRY(Core::TCPServer::try_create());