Fix format. Try compile on Windows.

examples/dom/separator.cpp

@@ -1,10 +1,11 @@
-#include "ftxui/screen/screen.hpp"
-#include "ftxui/dom/elements.hpp"
 #include <iostream>
 
-int main(int argc, const char *argv[])
-{
+#include "ftxui/dom/elements.hpp"
+#include "ftxui/screen/screen.hpp"
+
+int main(int argc, const char* argv[]) {
   using namespace ftxui;
+  // clang-format off
   auto document =
     hbox(
       text(L"left-column"),
@@ -17,6 +18,7 @@ int main(int argc, const char *argv[])
       separator(),
       text(L"right-column")
     ) | border;
+  // clang-format on
   auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());