Add link to matrix badge

Author: shiltemann

README.md

@@ -1,7 +1,7 @@
 <img src="./shared/images/GTNLogo1000.png" alt="GTN logo, a star on a coloured circle with the text Galaxy Training Network at an upward angle." width="400"  align="right" />
 
 # Galaxy Training Material 
-[![Deploy Website](https://github.com/galaxyproject/training-material/actions/workflows/deploy.yml/badge.svg)](https://github.com/galaxyproject/training-material/actions/workflows/deploy.yml) ![Matrix](https://img.shields.io/matrix/gtn:matrix.org)
+[![Deploy Website](https://github.com/galaxyproject/training-material/actions/workflows/deploy.yml/badge.svg)](https://github.com/galaxyproject/training-material/actions/workflows/deploy.yml) [![Matrix](https://img.shields.io/matrix/gtn:matrix.org)](https://matrix.to/#/#Galaxy-Training-Network_Lobby:gitter.im)
 
 
 This repository collects tutorials, slides, and exercises developed and maintained by the Galaxy community.