readme: remove main chat link (certificate expired)

README.md

@@ -1,6 +1,6 @@
 # Awesome-Selfhosted
 
-[![Awesome](https://cdn.rawgit.com/sindresorhus/awesome/d7305f38d29fed78fa85652e3a63e154dd8e8829/media/badge.svg)](https://github.com/sindresorhus/awesome) [![](https://camo.githubusercontent.com/3d659054abd6ce21c0e47cf3b83a51bda69ca282/68747470733a2f2f64656d6f2e726f636b65742e636861742f696d616765732f6a6f696e2d636861742e737667)](https://chat.awesh.unknownplus.com/channel/awesome-selfhosted)
+[![Awesome](https://cdn.rawgit.com/sindresorhus/awesome/d7305f38d29fed78fa85652e3a63e154dd8e8829/media/badge.svg)](https://github.com/sindresorhus/awesome)
 
 Selfhosting is the process of locally hosting and managing applications instead of renting from SaaS providers.