Update config.md

Update the URL of the reference of the config since this kind of global dynamic configuration is now moved to the `Dynamic Configuration Settings` web page, and the original URL responses 404 NOT FOUND.

doc/config.md

@@ -4,6 +4,6 @@ Config tab allows you to change your postgres configurations (it will be applied
 It doesn't rewrite all your config, it calls patches the existing configuration.
 If you want to remove (reset) some setting just patch it with `null`. 
 Be aware that some of the parameters requires a restart of postgres. 
-More information how it works you can find in patroni [site](https://patroni.readthedocs.io/en/latest/SETTINGS.html).
+More information how it works you can find in patroni [site](https://patroni.readthedocs.io/en/latest/dynamic_configuration.html).
 
 ![config](images/config.png)