Specify relation between matrix-registration and matrix-registration-bot

docs/configuring-playbook-matrix-registration.md

@@ -4,6 +4,8 @@ The playbook can install and configure [matrix-registration](https://github.com/
 
 **WARNING**: this is a poorly maintained and buggy project. It's better to avoid using it.
 
+**WARNING**: this is not related to [matrix-registration-bot](configuring-playbook-bot-matrix-registration-bot.md)
+
 > matrix-registration is a simple python application to have a token based matrix registration.
 
 Use matrix-registration to **create unique registration links**, which people can use to register on your Matrix server. It allows you to **keep your server's registration closed (private)**, but still allow certain people (these having a special link) to register a user account.