docs: Updated Services.md include chmod +x (#7230)

* docs: Updated added in chmod +x  (#0000)

* Update Services.md

* Update Services.md

doc/Extensions/Services.md

@@ -25,6 +25,10 @@ $config['nagios_plugins']   = "/usr/lib/nagios/plugins";
 ```
 
 This will point LibreNMS at the location of the nagios plugins - please ensure that any plugins you use are set to executable.
+For example: 
+```
+chmod +x /usr/lib/nagios/plugins/*
+```
 
 Finally, you now need to add check-services.php to the current cron file (/etc/cron.d/librenms typically) like:
 ```bash