Update Kokkos library in LAMMPS to v3.0

lib/kokkos/cmake/compile_tests/pthread.cpp

@@ -0,0 +1,10 @@
+#include <pthread.h>
+
+void* kokkos_test(void* args) { return args; }
+
+int main(void) {
+  pthread_t thread;
+  pthread_create(&thread, NULL, kokkos_test, NULL);
+  pthread_join(thread, NULL);
+  return 0;
+}