update badges in README

README.md

@@ -1,8 +1,9 @@
 # pyoperon
 
-[![License](https://img.shields.io/github/license/heal-research/pyoperon?style=flat)](https://github.com/heal-research/pyoperon/blob/master/LICENSE)
-[![build-linux](https://github.com/heal-research/pyoperon/actions/workflows/build-linux.yml/badge.svg?branch=cpp20)](https://github.com/heal-research/pyoperon/actions/workflows/build-linux.yml)
-[![Gitter chat](https://badges.gitter.im/operongp/gitter.png)](https://gitter.im/operongp/community)
+[![License](https://img.shields.io/github/license/heal-research/pyoperon)](https://github.com/heal-research/pyoperon/blob/master/LICENSE)
+[![Build-linux](https://github.com/heal-research/pyoperon/actions/workflows/build-linux.yml/badge.svg?branch=cpp20)](https://github.com/heal-research/pyoperon/actions/workflows/build-linux.yml)
+[![Build-macos](https://github.com/heal-research/pyoperon/actions/workflows/build-macos.yml/badge.svg?branch=cpp20)](https://github.com/heal-research/pyoperon/actions/workflows/build-linux.yml)
+[![Matrix chat](https://matrix.to/img/matrix-badge.svg)](https://matrix.to/#/#operon:matrix.org)
 
 **pyoperon** is the python bindings library of [**Operon**](https://github.com/heal-research/operon), a modern C++ framework for symbolic regression developed by [Heal-Research](https://github.com/heal-research) at the University of Applied Sciences Upper Austria.