Replace std::cout and std::cerr with fmt::print() (#3519)

ntcore/src/dev/native/cpp/main.cpp

@@ -2,7 +2,7 @@
 // Open Source Software; you can modify and/or share it under the terms of
 // the WPILib BSD license file in the root directory of this project.
 
-#include <iostream>
+#include <fmt/core.h>
 
 #include "ntcore.h"
 
@@ -11,5 +11,5 @@ int main() {
 
   nt::SetEntryValue(myValue, nt::Value::MakeString("Hello World"));
 
-  std::cout << nt::GetEntryValue(myValue)->GetString() << std::endl;
+  fmt::print("{}\n", nt::GetEntryValue(myValue)->GetString());
 }