fix some warnings (#660)

Co-authored-by: ArthurSonzogni <sonzogniarthur@gmail.com>

examples/component/menu_entries.cpp

@@ -28,7 +28,7 @@ MenuEntryOption Colored(ftxui::Color c) {
   return option;
 }
 
-int main(int argc, const char* argv[]) {
+int main() {
   auto screen = ScreenInteractive::TerminalOutput();
 
   int selected = 0;