Update Kokkos library in LAMMPS to v4.2

lib/kokkos/example/build_cmake_in_tree/cmake_example.cpp

@@ -15,7 +15,9 @@
 //@HEADER
 
 #include <Kokkos_Core.hpp>
+
 #include <cstdio>
+#include <iostream>
 
 int main(int argc, char* argv[]) {
   Kokkos::initialize(argc, argv);