Add a shorthand for ruby_debug_print_node

debug.c

@@ -155,6 +155,12 @@ ruby_debug_print_node(int level, int debug_level, const char *header, const NODE
     return (NODE *)node;
 }
 
+void
+ruby_debug_print_n(const NODE *node)
+{
+    ruby_debug_print_node(0, 1, "", node);
+}
+
 void
 ruby_debug_breakpoint(void)
 {