plugins/runcmd.c: Remove superfluous newline

The puts(3) function already appends a newline character to the string.

plugins/runcmd.c

@@ -261,7 +261,7 @@ runcmd_timeout_alarm_handler (int signo)
 	size_t i;
 
 	if (signo == SIGALRM)
-		puts(_("CRITICAL - Plugin timed out while executing system call\n"));
+		puts(_("CRITICAL - Plugin timed out while executing system call"));
 
 	if(np_pids) for(i = 0; i < maxfd; i++) {
 		if(np_pids[i] != 0) kill(np_pids[i], SIGKILL);