Multiple fixes: signed/unsigned, etc... (#600)

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

src/ftxui/component/terminal_input_parser_test.cpp

@@ -9,6 +9,7 @@
 #include "ftxui/component/receiver.hpp"  // for MakeReceiver, ReceiverImpl
 #include "ftxui/component/terminal_input_parser.hpp"
 
+// NOLINTBEGIN
 namespace ftxui {
 
 // Test char |c| to are trivially converted into |Event::Character(c)|.
@@ -384,6 +385,7 @@ TEST(Event, Special) {
 }
 
 }  // namespace ftxui
+// NOLINTEND
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in