Fix headings

README.md

@@ -10,6 +10,6 @@ Use the Deploy button above to launch n8n on Heroku. When deploying, make sure t
 
 The default credentials for basic authentication is `user:pass`, but you should change this during the initial setup.
 
-#### Enabling User Management
+## Enabling User Management
 
 The default configuration enables basic auth as a fast and simple way to authenticate n8n users. If you prefer the more advanced user management functionality of n8n, add the variables from [this guide](https://docs.n8n.io/hosting/user-management/) to your [Heroku config vars](https://devcenter.heroku.com/articles/config-vars#using-the-heroku-dashboard).