reference.mdx aktualisieren

Author: egelhaus

pages/configuration/reference.mdx

@@ -40,6 +40,10 @@ If running everything in the same host/container: `http://localhost:3000`
 
 Refer to the [example postiz.env file](https://raw.githubusercontent.com/gitroomhq/postiz-app/main/.env.example) for additional configuration options.
 
+### OAUTH
+
+See [this page](https://docs.postiz.com/configuration/oauth) for reference.
+
 ### DISABLE_REGISTRATION
 
 eg: `true`