Add missing includes for gcc

Bug:https://github.com/ArthurSonzogni/FTXUI/issues/695

include/ftxui/screen/string.hpp

@@ -2,6 +2,7 @@
 #define FTXUI_SCREEN_STRING_HPP
 
 #include <stddef.h>  // for size_t
+#include <cstdint>   // for uint8_t
 #include <string>    // for string, wstring, to_string
 #include <vector>    // for vector
 

src/ftxui/component/screen_interactive.cpp

@@ -70,7 +70,8 @@ void Flush() {
 }
 
 constexpr int timeout_milliseconds = 20;
-[[maybe_unused]] constexpr int timeout_microseconds = timeout_milliseconds * 1000;
+[[maybe_unused]] constexpr int timeout_microseconds =
+    timeout_milliseconds * 1000;
 #if defined(_WIN32)
 
 void EventListener(std::atomic<bool>* quit, Sender<Task> out) {

src/ftxui/component/slider.cpp

@@ -1,4 +1,5 @@
 #include <algorithm>  // for max, min
+#include <cstdint>    // for uint8_t, uint16_t, uint32_t, uint64_t
 #include <ftxui/component/component_options.hpp>  // for SliderOption
 #include <string>                                 // for allocator
 #include <utility>                                // for move

src/ftxui/screen/color.cpp

@@ -2,6 +2,7 @@
 
 #include <array>  // for array
 #include <cmath>
+#include <cstdint>
 #include <string_view>  // for literals
 
 #include "ftxui/screen/color_info.hpp"  // for GetColorInfo, ColorInfo

tools/license_headers.cpp

@@ -1,4 +1,4 @@
 
-// Copyright 2022 Arthur Sonzogni. All rights reserved.
+// Copyright 2023 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.