Fix Docker image link for matrix-registration

Related to 69f71f48

README.md

@@ -146,7 +146,7 @@ This playbook sets up your server using the following Docker images:
 
 - [devture/matrix-corporal](https://hub.docker.com/r/devture/matrix-corporal/) - [Matrix Corporal](https://github.com/devture/matrix-corporal): reconciliator and gateway for a managed Matrix server (optional)
 
-- [devture/zeratax-matrix-registration](https://hub.docker.com/r/devture/zeratax-matrix-registration/) - [matrix-registration](https://github.com/ZerataX/matrix-registration): a simple python application to have a token based matrix registration (optional)
+- [zeratax/matrix-registration](https://hub.docker.com/r/devture/zeratax-matrix-registration/) - [matrix-registration](https://github.com/ZerataX/matrix-registration): a simple python application to have a token based matrix registration (optional)
 
 - [nginx](https://hub.docker.com/_/nginx/) - the [nginx](http://nginx.org/) web server (optional)